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Sample records for active ebv infection

  1. Quercetin-induced apoptosis prevents EBV infection.

    PubMed

    Lee, Minjung; Son, Myoungki; Ryu, Eunhyun; Shin, Yu Su; Kim, Jong Gwang; Kang, Byung Woog; Cho, Hyosun; Kang, Hyojeung

    2015-05-20

    Epstein-Barr virus (EBV) is a human gamma-1 herpesvirus that establishes a lifelong latency in over 90% of the world's population. During latency, virus exists predominantly as a chromatin-associated, multicopy episome in the nuclei of a variety of tumor cells derived from B cells, T cells, natural killer (NK) cells, and epithelial cells. Licorice is the root of Glycyrrhiza uralensis or G. glabra that has traditionally cultivated in eastern part of Asia. Licorice was reported to have anti-viral, anti-inflammatory, anti-atopic, hepatoprotective, anti-neurodegenerative, anti-tumor, anti-diabetic effects and so forth. Quercetin and isoliquiritigenin are produced from licorice and highly similar in molecular structure. They have diverse bioactive effects such as antiviral activity, anti-asthmatic activity, anti-cancer activity, anti-inflammation activity, monoamine-oxidase inhibitor, and etc. To determine anti-EBV and anti-EBVaGC (Epstein-Barr virus associated gastric carcinoma) effects of licorice, we investigated antitumor and antiviral effects of quercetin and isoliquiritigenin against EBVaGC. Although both quercetin and isoliquiritigenin are cytotoxic to SNU719 cells, quercetin induced more apoptosis in SNU719 cells than isoliquiritigenin, more completely eliminated DNMT1 and DNMT3A expressions than isoliquiritigenin, and more strongly affects the cell cycle progression of SNU719 than isoliquiritigenin. Both quercetin and isoliquiritigenin induce signal transductions to stimulate apoptosis, and induce EBV gene transcription. Quercetin enhances frequency of F promoter use, whereas isoliquiritigenin enhances frequency of Q promoter use. Quercetin reduces EBV latency, whereas isoliquiritigenin increases the latency. Quercetin increases more the EBV progeny production, and inhibits more EBV infection than isoliquiritigenin. These results indicate that quercetin could be a promising candidate for antiviral and antitumor agents against EBV and human gastric carcinoma.

  2. Quercetin-induced apoptosis prevents EBV infection

    PubMed Central

    Lee, Minjung; Son, Myoungki; Ryu, Eunhyun; Shin, Yu Su; Kim, Jong Gwang; Kang, Byung Woog; Sung, Gi-Ho; Cho, Hyosun; Kang, Hyojeung

    2015-01-01

    Epstein-Barr virus (EBV) is a human gamma-1 herpesvirus that establishes a lifelong latency in over 90% of the world's population. During latency, virus exists predominantly as a chromatin-associated, multicopy episome in the nuclei of a variety of tumor cells derived from B cells, T cells, natural killer (NK) cells, and epithelial cells. Licorice is the root of Glycyrrhiza uralensis or G. glabra that has traditionally cultivated in eastern part of Asia. Licorice was reported to have anti-viral, anti-inflammatory, anti-atopic, hepatoprotective, anti-neurodegenerative, anti-tumor, anti-diabetic effects and so forth. Quercetin and isoliquiritigenin are produced from licorice and highly similar in molecular structure. They have diverse bioactive effects such as antiviral activity, anti-asthmatic activity, anti-cancer activity, anti-inflammation activity, monoamine-oxidase inhibitor, and etc. To determine anti-EBV and anti-EBVaGC (Epstein-Barr virus associated gastric carcinoma) effects of licorice, we investigated antitumor and antiviral effects of quercetin and isoliquiritigenin against EBVaGC. Although both quercetin and isoliquiritigenin are cytotoxic to SNU719 cells, quercetin induced more apoptosis in SNU719 cells than isoliquiritigenin, more completely eliminated DNMT1 and DNMT3A expressions than isoliquiritigenin, and more strongly affects the cell cycle progression of SNU719 than isoliquiritigenin. Both quercetin and isoliquiritigenin induce signal transductions to stimulate apoptosis, and induce EBV gene transcription. Quercetin enhances frequency of F promoter use, whereas isoliquiritigenin enhances frequency of Q promoter use. Quercetin reduces EBV latency, whereas isoliquiritigenin increases the latency. Quercetin increases more the EBV progeny production, and inhibits more EBV infection than isoliquiritigenin. These results indicate that quercetin could be a promising candidate for antiviral and antitumor agents against EBV and human gastric carcinoma

  3. Genipin as a novel chemical activator of EBV lytic cycle.

    PubMed

    Son, Myoungki; Lee, Minjung; Ryu, Eunhyun; Moon, Aree; Jeong, Choon-Sik; Jung, Yong Woo; Park, Gyu Hwan; Sung, Gi-Ho; Cho, Hyosun; Kang, Hyojeung

    2015-02-01

    Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that causes acute infection and establishes life-long latency. EBV causes several human cancers, including Burkitt's lymphoma, nasopharyngeal and gastric carcinoma. Antiviral agents can be categorized as virucides, antiviral chemotherapeutic agents, and immunomodulators. Most antiviral agents affect actively replicating viruses, but not their latent forms. Novel antiviral agents must be active on both the replicating and the latent forms of the virus. Gardenia jasminoides is an evergreen flowering plant belonging to the Rubiaceae family and is most commonly found growing wild in Vietnam, Southern China, Taiwan, Japan, Myanmar, and India. Genipin is an aglycone derived from an iridoid glycoside called geniposide, which is present in large quantities in the fruit of G. jasminoides. In this study, genipin was evaluated for its role as an antitumor and antiviral agent that produces inhibitory effects against EBV and EBV associated gastric carcinoma (EBVaGC). In SNU719 cells, one of EBVaGCs, genipin caused significant cytotoxicity (70 μM), induced methylation on EBV C promoter and tumor suppressor gene BCL7A, arrested cell-cycle progress (S phases), upregulated EBV latent/lytic genes in a dose-dependent manner, stimulated EBV progeny production, activated EBV F promoter for EBV lytic activation, and suppressed EBV infection. These results indicated that genipin could be a promising candidate for antiviral and antitumor agents against EBV and EBVaGC. PMID:25626372

  4. Genipin as a novel chemical activator of EBV lytic cycle.

    PubMed

    Son, Myoungki; Lee, Minjung; Ryu, Eunhyun; Moon, Aree; Jeong, Choon-Sik; Jung, Yong Woo; Park, Gyu Hwan; Sung, Gi-Ho; Cho, Hyosun; Kang, Hyojeung

    2015-02-01

    Epstein-Barr virus (EBV) is a ubiquitous gammaherpesvirus that causes acute infection and establishes life-long latency. EBV causes several human cancers, including Burkitt's lymphoma, nasopharyngeal and gastric carcinoma. Antiviral agents can be categorized as virucides, antiviral chemotherapeutic agents, and immunomodulators. Most antiviral agents affect actively replicating viruses, but not their latent forms. Novel antiviral agents must be active on both the replicating and the latent forms of the virus. Gardenia jasminoides is an evergreen flowering plant belonging to the Rubiaceae family and is most commonly found growing wild in Vietnam, Southern China, Taiwan, Japan, Myanmar, and India. Genipin is an aglycone derived from an iridoid glycoside called geniposide, which is present in large quantities in the fruit of G. jasminoides. In this study, genipin was evaluated for its role as an antitumor and antiviral agent that produces inhibitory effects against EBV and EBV associated gastric carcinoma (EBVaGC). In SNU719 cells, one of EBVaGCs, genipin caused significant cytotoxicity (70 μM), induced methylation on EBV C promoter and tumor suppressor gene BCL7A, arrested cell-cycle progress (S phases), upregulated EBV latent/lytic genes in a dose-dependent manner, stimulated EBV progeny production, activated EBV F promoter for EBV lytic activation, and suppressed EBV infection. These results indicated that genipin could be a promising candidate for antiviral and antitumor agents against EBV and EBVaGC.

  5. Neuropilin 1 is an entry factor that promotes EBV infection of nasopharyngeal epithelial cells

    PubMed Central

    Wang, Hong-Bo; Zhang, Hua; Zhang, Jing-Ping; Li, Yan; Zhao, Bo; Feng, Guo-Kai; Du, Yong; Xiong, Dan; Zhong, Qian; Liu, Wan-Li; Du, Huamao; Li, Man-Zhi; Huang, Wen-Lin; Tsao, Sai Wah; Hutt-Fletcher, Lindsey; Zeng, Yi-Xin; Kieff, Elliott; Zeng, Mu-Sheng

    2015-01-01

    Epstein–Barr virus (EBV) is implicated as an aetiological factor in B lymphomas and nasopharyngeal carcinoma. The mechanisms of cell-free EBV infection of nasopharyngeal epithelial cells remain elusive. EBV glycoprotein B (gB) is the critical fusion protein for infection of both B and epithelial cells, and determines EBV susceptibility of non-B cells. Here we show that neuropilin 1 (NRP1) directly interacts with EBV gB23–431. Either knockdown of NRP1 or pretreatment of EBV with soluble NRP1 suppresses EBV infection. Upregulation of NRP1 by overexpression or EGF treatment enhances EBV infection. However, NRP2, the homologue of NRP1, impairs EBV infection. EBV enters nasopharyngeal epithelial cells through NRP1-facilitated internalization and fusion, and through macropinocytosis and lipid raft-dependent endocytosis. NRP1 partially mediates EBV-activated EGFR/RAS/ERK signalling, and NRP1-dependent receptor tyrosine kinase (RTK) signalling promotes EBV infection. Taken together, NRP1 is identified as an EBV entry factor that cooperatively activates RTK signalling, which subsequently promotes EBV infection in nasopharyngeal epithelial cells. PMID:25670642

  6. Kinetics of Epstein-Barr Virus (EBV) Neutralizing and Virus-Specific Antibodies after Primary Infection with EBV

    PubMed Central

    Bu, Wei; Hayes, Gregory M.; Liu, Hui; Gemmell, Lorraine; Schmeling, David O.; Radecki, Pierce; Aguilar, Fiona; Burbelo, Peter D.; Woo, Jennifer; Balfour, Henry H.

    2016-01-01

    Prospective studies of antibodies to multiple Epstein-Barr virus (EBV) proteins and EBV neutralizing antibodies in the same individuals before, during, and after primary EBV infection have not been reported. We studied antibody responses to EBV in college students who acquired primary EBV infection during prospective surveillance and correlated the kinetics of antibody response with the severity of disease. Neutralizing antibodies and enzyme-linked immunosorbent assay (ELISA) antibodies to gp350, the major target of neutralizing antibody, reached peak levels at medians of 179 and 333 days after the onset of symptoms of infectious mononucleosis, respectively. No clear correlation was found between the severity of the symptoms of infectious mononucleosis and the peak levels of antibody to individual viral proteins or to neutralizing antibody. In summary, we found that titers of neutralizing antibody and antibodies to multiple EBV proteins increase over many months after primary infection with EBV. PMID:26888186

  7. Latent Membrane Protein LMP2A Impairs Recognition of EBV-Infected Cells by CD8+ T Cells.

    PubMed

    Rancan, Chiara; Schirrmann, Leah; Hüls, Corinna; Zeidler, Reinhard; Moosmann, Andreas

    2015-06-01

    The common pathogen Epstein-Barr virus (EBV) transforms normal human B cells and can cause cancer. Latent membrane protein 2A (LMP2A) of EBV supports activation and proliferation of infected B cells and is expressed in many types of EBV-associated cancer. It is not clear how latent EBV infection and cancer escape elimination by host immunity, and it is unknown whether LMP2A can influence the interaction of EBV-infected cells with the immune system. We infected primary B cells with EBV deleted for LMP2A, and established lymphoblastoid cell lines (LCLs). We found that CD8+ T cell clones showed higher reactivity against LMP2A-deficient LCLs compared to LCLs infected with complete EBV. We identified several potential mediators of this immunomodulatory effect. In the absence of LMP2A, expression of some EBV latent antigens was elevated, and cell surface expression of MHC class I was marginally increased. LMP2A-deficient LCLs produced lower amounts of IL-10, although this did not directly affect CD8+ T cell recognition. Deletion of LMP2A led to several changes in the cell surface immunophenotype of LCLs. Specifically, the agonistic NKG2D ligands MICA and ULBP4 were increased. Blocking experiments showed that NKG2D activation contributed to LCL recognition by CD8+ T cell clones. Our results demonstrate that LMP2A reduces the reactivity of CD8+ T cells against EBV-infected cells, and we identify several relevant mechanisms.

  8. Simultaneous genital ulcer and meningitis: a case of EBV infection

    PubMed Central

    Nunes, Jairo Tavares; Lopes, Leonardo da Costa; Prokopowitsch, Aleksander Snioka

    2016-01-01

    The Epstein-Barr virus (EBV) is associated with a broad spectrum of diseases, mainly because of its genomic characteristics, which result in different latency patterns in immune cells and infective mechanisms. The patient described in this report is a previously healthy young man who presented to the emergency department with clinical features consistent with meningitis and genital ulcers, which raised concern that the herpes simplex virus was the causative agent. However, the polymerase chain reaction of cerebral spinal fluid was positive for EBV. The authors highlight the importance of this infection among the differential diagnosis of central nervous system involvement and genital ulceration. PMID:27547743

  9. CUX1/Wnt signaling regulates Epithelial Mesenchymal Transition in EBV infected epithelial cells

    SciTech Connect

    Malizia, Andrea P.; Lacey, Noreen; Walls, Dermot; Egan, Jim J.; Doran, Peter P.

    2009-07-01

    Idiopathic pulmonary fibrosis (IPF) is a refractory and lethal interstitial lung disease characterized by alveolar epithelial cells apoptosis, fibroblast proliferation and extra-cellular matrix protein deposition. EBV, localised to alveolar epithelial cells of pulmonary fibrosis patients is associated with a poor prognosis. A strategy based on microarray-differential gene expression analysis to identify molecular drivers of EBV-associated lung fibrosis was utilized. Alveolar epithelial cells were infected with EBV to identify genes whose expression was altered following TGF{beta}1-mediated lytic phase. EBV lytic reactivation by TGF{beta}1 drives a selective alteration in CUX1 variant (a) (NCBI accession number NM{sub 1}81552) expression, inducing activation of non-canonical Wnt pathway mediators, implicating it in Epithelial Mesenchymal Transition (EMT), the molecular event underpinning scar production in tissue fibrosis. The role of EBV in EMT can be attenuated by antiviral strategies and inhibition of Wnt signaling by using All-Trans Retinoic Acids (ATRA). Activation of non-canonical Wnt signaling pathway by EBV in epithelial cells suggests a novel mechanism of EMT via CUX1 signaling. These data present a framework for further description of the link between infectious agents and fibrosis, a significant disease burden.

  10. HPV Infection, but Not EBV or HHV-8 Infection, Is Associated with Salivary Gland Tumours

    PubMed Central

    Hühns, Maja; Simm, Georg; Erbersdobler, Andreas; Zimpfer, Annette

    2015-01-01

    Benign and malignant salivary gland tumours are clinically heterogeneous and show different histology. Little is known about the role of human herpes virus 8 (HHV-8), Epstein-Barr virus (EBV), and human papillomavirus (HPV) infection in salivary gland neoplasms. We investigated the presence of the three viruses in formalin-fixed, paraffin-embedded tissue samples in a cohort of 200 different salivary gland tumours. We performed EBV-LMP-1 and HHV-8 and p16 immunohistochemistry, a specific chip based hybridization assay for detection and typing of HPV and a chromogenic in situ hybridization for EBV analysis. Only one case, a polymorphic low-grade carcinoma, showed HHV-8 expression and one lymphoepithelial carcinoma was infected by EBV. In 17 cases (9%) moderate or strong nuclear and cytoplasmic p16 expression was detected. The HPV type was investigated in all of these cases and additionally in 8 Warthin's tumours. In 19 cases HPV type 16 was detected, mostly in Warthin's tumour, adenoid cystic carcinoma, and adenocarcinoma NOS. We concluded that HHV-8 infection and EBV infection are not associated with salivary gland cancer, but HPV infection may play a role in these tumour entities. PMID:26618178

  11. HPV Infection, but Not EBV or HHV-8 Infection, Is Associated with Salivary Gland Tumours.

    PubMed

    Hühns, Maja; Simm, Georg; Erbersdobler, Andreas; Zimpfer, Annette

    2015-01-01

    Benign and malignant salivary gland tumours are clinically heterogeneous and show different histology. Little is known about the role of human herpes virus 8 (HHV-8), Epstein-Barr virus (EBV), and human papillomavirus (HPV) infection in salivary gland neoplasms. We investigated the presence of the three viruses in formalin-fixed, paraffin-embedded tissue samples in a cohort of 200 different salivary gland tumours. We performed EBV-LMP-1 and HHV-8 and p16 immunohistochemistry, a specific chip based hybridization assay for detection and typing of HPV and a chromogenic in situ hybridization for EBV analysis. Only one case, a polymorphic low-grade carcinoma, showed HHV-8 expression and one lymphoepithelial carcinoma was infected by EBV. In 17 cases (9%) moderate or strong nuclear and cytoplasmic p16 expression was detected. The HPV type was investigated in all of these cases and additionally in 8 Warthin's tumours. In 19 cases HPV type 16 was detected, mostly in Warthin's tumour, adenoid cystic carcinoma, and adenocarcinoma NOS. We concluded that HHV-8 infection and EBV infection are not associated with salivary gland cancer, but HPV infection may play a role in these tumour entities.

  12. Combination of immunoglobulins and natural killer cells in the context of CMV and EBV infection.

    PubMed

    Frenzel, K; Lehmann, J; Krüger, D H; Martin-Parras, L; Uharek, L; Hofmann, J

    2014-04-01

    Cytomegalovirus (CMV)-specific hyperimmunoglobulin (CMV-HIG) is used to treat and prevent CMV infection in immunocompromised patients, and anti-CD20 monoclonal antibody is successfully used in the treatment for post-transplant lymphoproliferative disease caused by Epstein-Barr virus (EBV). Two immunological approaches have been suggested to further improve the control of viral reproduction in patients with active disease: first, the use of monoclonal antibodies with specificity against viral epitopes and second, coadministration of cells with the capacity to promote antibody-dependent cell-mediated cytotoxicity. Here, we have evaluated the effectiveness of these strategies in vitro (alone and in combination) with neutralization and cytotoxicity assays. Our results indicate that monoclonal antibodies (in particular SM5-1) can be as effective as CMV-HIG in neutralizing-cell-free CMV. Moreover, our data indicate that antibody-mediated elimination (either by moAb or by HIG) of EBV-infected cells can be significantly enhanced by NK cells. Using human NK cells that have been purified, cultured and expanded under GMP conditions, we were able to demonstrate that the combination of NK cells and antibodies could represent a feasible and highly effective clinical approach to achieve control of EBV infections. Especially in leukopenic patients with low numbers of ADCC-promoting cells, the combination of adoptively transferred NK cells and antiviral antibodies offers a promising strategy that should be tested in clinical trials.

  13. NF-kappaB is essential for the progression of KSHV- and EBV-infected lymphomas in vivo.

    PubMed

    Keller, Shannon A; Hernandez-Hopkins, Denise; Vider, Jelena; Ponomarev, Vladimir; Hyjek, Elizabeth; Schattner, Elaine J; Cesarman, Ethel

    2006-04-15

    Activated NF-kappaB is a critical mechanism by which lymphoma cells infected by Epstein-Barr virus (EBV/HHV-4) and Kaposi sarcoma herpesvirus (KSHV/HHV-8) are protected from apoptotic stress. Selective pharmacologic inhibition of constitutive NF-kappaB activity induces apoptosis in KSHV- and EBV-infected lymphoma cells. In both tumor types, pharmacologic inhibition of NF-kappaB in vitro induced identical mitochondrially mediated apoptosis cascades. Assessment of gene regulation by microarray analysis revealed that the inhibition of NF-kappaB in tumor cells results in the down-regulation of a distinct group of prosurvival genes, including cIAP-1, cIAP-2, cFLIP, and IL-6. Using EBV- and KSHV-associated lymphomas in a murine system, we demonstrated that Bay 11-7082, a selective pharmacologic inhibitor of NF-kappaB, prevents or delays tumor growth and prolongs disease-free survival. Inhibition of NF-kappaB activity and tumor growth responses were further documented using a traceable reporter KSHV-positive cell line and in vivo imaging. These findings indicate that specific NF-kappaB-regulated survival factors work cooperatively to protect KSHV- and EBV-infected lymphoma cells from apoptosis such that they promote the establishment and progression of KSHV- and EBV-associated lymphomas in mice. They also support the use of selective NF-kappaB inhibitors in the treatment of herpesvirus-associated lymphomas.

  14. Innate immune control of EBV-infected B cells by invariant natural killer T cells.

    PubMed

    Chung, Brian K; Tsai, Kevin; Allan, Lenka L; Zheng, Dong Jun; Nie, Johnny C; Biggs, Catherine M; Hasan, Mohammad R; Kozak, Frederick K; van den Elzen, Peter; Priatel, John J; Tan, Rusung

    2013-10-10

    Individuals with X-linked lymphoproliferative disease lack invariant natural killer T (iNKT) cells and are exquisitely susceptible to Epstein-Barr virus (EBV) infection. To determine whether iNKT cells recognize or regulate EBV, resting B cells were infected with EBV in the presence or absence of iNKT cells. The depletion of iNKT cells increased both viral titers and the frequency of EBV-infected B cells. However, EBV-infected B cells rapidly lost expression of the iNKT cell receptor ligand CD1d, abrogating iNKT cell recognition. To determine whether induced CD1d expression could restore iNKT recognition in EBV-infected cells, lymphoblastoid cell lines (LCL) were treated with AM580, a synthetic retinoic acid receptor-α agonist that upregulates CD1d expression via the nuclear protein, lymphoid enhancer-binding factor 1 (LEF-1). AM580 significantly reduced LEF-1 association at the CD1d promoter region, induced CD1d expression on LCL, and restored iNKT recognition of LCL. CD1d-expressing LCL elicited interferon γ secretion and cytotoxicity by iNKT cells even in the absence of exogenous antigen, suggesting an endogenous iNKT antigen is expressed during EBV infection. These data indicate that iNKT cells may be important for early, innate control of B cell infection by EBV and that downregulation of CD1d may allow EBV to circumvent iNKT cell-mediated immune recognition.

  15. PKC theta and p38 MAPK activate the EBV lytic cycle through autophagy induction.

    PubMed

    Gonnella, Roberta; Granato, Marisa; Farina, Antonella; Santarelli, Roberta; Faggioni, Alberto; Cirone, Mara

    2015-07-01

    PKC activation by combining TPA with sodium butyrate (T/B) represents the most effective and widely used strategy to induce the Epstein-Barr virus (EBV) lytic cycle. The results obtained in this study show that novel PKCθ is involved in such process and that it acts through the activation of p38 MAPK and autophagy induction. Autophagy, a mechanism of cellular defense in stressful conditions, is manipulated by EBV to enhance viral replication. Besides promoting the EBV lytic cycle, the activation of p38 and autophagy resulted in a pro-survival effect, as indicated by p38 or ATG5 knocking down experiments. However, this pro-survival role was counteracted by a pro-death activity of PKCθ, due to the dephosphorylation of AKT. In conclusion, this study reports, for the first time, that T/B activates a PKCθ-p38 MAPK axis in EBV infected B cells, that promotes the viral lytic cycle and cell survival and dephosphorylates AKT, balancing cell life and cell death. PMID:25827954

  16. PKC theta and p38 MAPK activate the EBV lytic cycle through autophagy induction.

    PubMed

    Gonnella, Roberta; Granato, Marisa; Farina, Antonella; Santarelli, Roberta; Faggioni, Alberto; Cirone, Mara

    2015-07-01

    PKC activation by combining TPA with sodium butyrate (T/B) represents the most effective and widely used strategy to induce the Epstein-Barr virus (EBV) lytic cycle. The results obtained in this study show that novel PKCθ is involved in such process and that it acts through the activation of p38 MAPK and autophagy induction. Autophagy, a mechanism of cellular defense in stressful conditions, is manipulated by EBV to enhance viral replication. Besides promoting the EBV lytic cycle, the activation of p38 and autophagy resulted in a pro-survival effect, as indicated by p38 or ATG5 knocking down experiments. However, this pro-survival role was counteracted by a pro-death activity of PKCθ, due to the dephosphorylation of AKT. In conclusion, this study reports, for the first time, that T/B activates a PKCθ-p38 MAPK axis in EBV infected B cells, that promotes the viral lytic cycle and cell survival and dephosphorylates AKT, balancing cell life and cell death.

  17. Oligo-monoclonal immunoglobulins frequently develop during concurrent cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections in patients after renal transplantation.

    PubMed

    Drouet, E; Chapuis-Cellier, C; Bosshard, S; Verniol, C; Niveleau, A; Touraine, J L; Garnier, J L

    1999-12-01

    In the present study we report that the appearance of oligo-monoclonal immunoglobulins (oligoM-Igs) in the sera of transplanted individuals is concurrent with the detection of coincident active CMV infection and EBV replication. Eighty-four renal allograft patients were monitored with respect to CMV isolation, to CMV conventional serology and humoral response against the EBV trans-activator ZEBRA (an immediate-early antigen also called BZLF1). Titration of anti-ZEBRA antibodies (IgG and IgM) and amount of EBV DNA in serum were evaluated. Using the combination of four techniques (agarose gel electrophoresis, analytical isoelectric focusing, high resolution immunoelectrophoresis, immunofixation electrophoresis), oligoM-Igs were found in 25% of patients after allografting and significantly associated with rejection episodes (P < 0.001). Twenty out of 23 (86%) concurrent CMV/EBV infections were associated with serum oligoM-Igs (P < 0.001). One can thus reasonably assume that a sustained EBV replication following iatrogenic immunosuppression can promote the immunoglobulin heavy chain expression in EBV-infected B lymphocytes. The proliferation of immunoglobulin-secreting clones might occur after active CMV infection, through a transient over-immunosuppression or via immune subversion.

  18. Oropharyngeal malignant epithelial cell, lymphocyte and macrophage CD44 surface receptors for hyaluronate are expressed in sustained EBV infection: immunohistochemical data and EBV DNA tissue indices.

    PubMed

    Groma, Valerija; Kazanceva, Anna; Nora-Krukle, Zaiga; Murovska, Modra

    2012-09-15

    The role of CD44 in Epstein-Barr virus (EBV)-related epithelial tumors is poorly understood. We studied the expression of CD44 in EBV infection in patients with oral squamous cell carcinoma (SCC) and nasopharyngeal carcinoma (NPC) and measured the EBV DNA. Whole blood, plasma and tissue samples from 8 male and 2 female patients with oral SCC, NPC, salivary gland lymphoepithelioma, normal salivary gland and buccal mucosa were assayed for EBV DNA. Expression of CD44, latent membrane protein (LMP), and labeling of lymphocytes, macrophages and dendritic cells were estimated by immunohistochemistry. Tissue EBV DNA was detected in 7 of 8 cases (87.5%) of oral malignant, benign and border-line lesions. LMP expression levels in tumors varied from absence and minimal to moderate - 50.3, 43.6, 6.0% and 91.1, 6.7, 2.2% for SCC and NPC, respectively. Levels of CD44 positivity in neoplasms were minimal (15.5 and 16.7%), moderate (30.3 and 47.8%), and diffuse (54.2 and 35.5%) for SCC and NPC, respectively, thus deviating from normal oral mucosa revealing heavily stained (100.0%) epithelial contours. CD19-positive B lymphocytes and S100-positive dendritic cells were intermixed with neoplastic cells. Collectively, CD44 mediated signaling may be implicated in EBV infection associated with the pathogenesis of oral SCC and NPC.

  19. Correlation between ebv co-infection and HPV16 genome integrity in Tunisian cervical cancer patients

    PubMed Central

    Kahla, Saloua; Oueslati, Sarra; Achour, Mongia; Kochbati, Lotfi; Chanoufi, Mohamed Badis; Maalej, Mongi; Oueslati, Ridha

    2012-01-01

    Infection with high risk Human papillomavirus (HR-HPV) is necessary but not sufficient to cause cervical carcinoma. This study explored whether multiple HR-HPV or coinfection with Epstein-Barr virus (EBV) influence the integration status of HPV16 genome. The presence and typing of HPV in a series of 125 cervical specimens were assessed by polymerase chain reaction (PCR) using the specific primers for the HPV L1 region. As for EBV infection, the viral EBNA1 gene was used for its detection through PCR amplification. Disruption of the HPV E2 gene was assessed by amplification of the entire E2 gene with single set of primers, while E2 transcripts were evaluated by a reverse transcription PCR method (RT-PCR). The overall prevalence of HPVDNA was of 81.8% in cervical cancers versus 26.9% in benign lesions. In HPV positive cases, HPV16 and HPV18 were the most prevalent types, followed by HPV types 33, 31. EBV EBNA1 prevalence was statistically more frequent in cervical carcinomas than in benign lesions (29.5%, vs 9.6%; P=0.01). No viral infection was detected in healthy control women. The uninterrupted E2 gene was correlated with the presence of E2 transcripts originating from the HPV episomal forms. It was observed that integration was more common in HPV18 and EBV coinfection. The presence of EBV caused a five-fold [OR= 5; CI= 1.15-21.8; P = 0.04] increase in the risk of HPV16 genome integration in the host genome. This study indicates that EBV infection is acting as a cofactor for induction of cervical cancer by favoring HPVDNA integration. PMID:24031886

  20. EBV-Positive Grey Zone Lymphoma in an HIV Infected Man from Kampala, Uganda: Case Report

    PubMed Central

    Tumwine, Lynette K.; Orem, Jackson; Ayers, Leona W.

    2014-01-01

    Aim We describe the clinical, histopathological and immunophenotypic characteristics of an HIV-infected adult man on antiretroviral therapy who presented with an EBV-positive grey zone lymphoma. Case presentation A 56-year-old HIV infected man from Uganda presented with a four month history of progressive abdominal swelling and B-symptoms. He was on highly active antiretroviral therapy (HAART) and cotrimoxazole. He was afebrile (36.9°C), severely wasted (BMI 14.8), and mildly anaemic. On physical examination, he had a 15 by 8 cm mass in the hypogastrium and umbilical region. The total white cell count was 8.3×103/μL; neutrophils, 5.72×103/μL; haemoglobin 11.1g/dL, platelets 528×103/μL, LDH 197 IU/L and CD4 367/μL. Abdominal ultrasound and CT scan showed a tumour involving the mesentery, jejunum and mid ileum. At laparotomy, a biopsy was taken, fixed, processed and stained with Haematoxylin & Eosin (H & E). Histopathology demonstrated large pleomorphic cells admixed with inflammatory smaller cells, Reed-Sternberg-like cell variants and frequent abnormal mitoses. Biomarkers CD20, PAX5, CD30 were positive but ALK negative (immunohistochemistry and strong EBER positivity in situ hybridization. The patient improved on modified CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisolone) therapy. Discussion The tumour had features intermediate between mediastinal large B cell lymphoma and classical Hodgkin lymphoma. Conclusion We present a case of EBV-positive grey zone lymphoma in an HIV-infected man on HAART therapy diagnosed and treated in a resource constrained medical setting. The histological features are unusual and represent a low incidence lymphoma that is recognized by mixed features reminiscent of Hodgkin’s lymphoma and mediastinal large B-cell lymphoma. PMID:25599090

  1. Differences in Gastric Carcinoma Microenvironment Stratify According to EBV Infection Intensity: Implications for Possible Immune Adjuvant Therapy

    PubMed Central

    Coco, Joseph; Baribault, Carl; Vinay, Dass S.; Lacey, Michelle R.; Strong, Amy L.; Lehman, Teresa A.; Seddon, Michael B.; Lin, Zhen; Concha, Monica; Baddoo, Melody; Ferris, MaryBeth; Swan, Kenneth F.; Sullivan, Deborah E.; Burow, Matthew E.; Taylor, Christopher M.; Flemington, Erik K.

    2013-01-01

    Epstein-Barr virus (EBV) is associated with roughly 10% of gastric carcinomas worldwide (EBVaGC). Although previous investigations provide a strong link between EBV and gastric carcinomas, these studies were performed using selected EBV gene probes. Using a cohort of gastric carcinoma RNA-seq data sets from The Cancer Genome Atlas (TCGA), we performed a quantitative and global assessment of EBV gene expression in gastric carcinomas and assessed EBV associated cellular pathway alterations. EBV transcripts were detected in 17% of samples but these samples varied significantly in EBV coverage depth. In four samples with the highest EBV coverage (hiEBVaGC – high EBV associated gastric carcinoma), transcripts from the BamHI A region comprised the majority of EBV reads. Expression of LMP2, and to a lesser extent, LMP1 were also observed as was evidence of abortive lytic replication. Analysis of cellular gene expression indicated significant immune cell infiltration and a predominant IFNG response in samples expressing high levels of EBV transcripts relative to samples expressing low or no EBV transcripts. Despite the apparent immune cell infiltration, high levels of the cytotoxic T-cell (CTL) and natural killer (NK) cell inhibitor, IDO1, was observed in the hiEBVaGCs samples suggesting an active tolerance inducing pathway in this subgroup. These results were confirmed in a separate cohort of 21 Vietnamese gastric carcinoma samples using qRT-PCR and on tissue samples using in situ hybridization and immunohistochemistry. Lastly, a panel of tumor suppressors and candidate oncogenes were expressed at lower levels in hiEBVaGC versus EBV-low and EBV-negative gastric cancers suggesting the direct regulation of tumor pathways by EBV. PMID:23671415

  2. The clinical significance of EBV DNA in the plasma and peripheral blood mononuclear cells of patients with or without EBV diseases.

    PubMed

    Kanakry, Jennifer A; Hegde, Aparna M; Durand, Christine M; Massie, Allan B; Greer, Amy E; Ambinder, Richard F; Valsamakis, Alexandra

    2016-04-21

    Epstein-Barr virus (EBV) is a ubiquitous virus that establishes a latent infection within the host and in some cases can lead to the development of EBV-associated lymphomas, lymphoproliferative disorders, hemophagocytic lymphohistiocytosis, solid tumors, and other diseases. We studied the clinical significance of detecting EBV DNA in the plasma and peripheral blood mononuclear cells (PBMCs) of 2146 patients who had blood specimens sent to the Johns Hopkins Hospital clinical laboratory for viral quantitative real-time polymerase chain reaction assay over a 5-year period. Within this largely immunocompromised and hospitalized cohort, 535 patients (25%) had EBV detected in plasma or PBMCs. When EBV was detected in the absence of an EBV(+)disease (n = 402), it was present only in PBMCs in 69% of cases. Immunocompromised patients were less likely to have EBV in plasma than in PBMCs in the absence of EBV(+)disease. In patients with active, systemic EBV(+)diseases (n = 105), EBV was detected in plasma in 99% of cases but detected in PBMCs in only 54%. Across a range of copy number cutoffs, EBV in plasma had higher specificity and sensitivity for EBV(+)disease as compared with EBV in PBMCs. EBV copy number in plasma distinguished untreated, EBV(+)lymphoma from EBV(+)lymphoma in remission and EBV(-)lymphoma, and also distinguished untreated, EBV(+)posttransplantation lymphoproliferative disorder (PTLD) from EBV(+)PTLD in remission and EBV(-)PTLD. EBV copy number quantification is a useful diagnostic marker across the spectrum of EBV(+)diseases, even among immunocompromised patients, with plasma specimens more indicative of EBV(+)disease than PBMCs.

  3. Invasive Fusobacterium necrophorum infections and Lemièrre's syndrome: the role of thrombophilia and EBV.

    PubMed

    Holm, K; Svensson, P J; Rasmussen, M

    2015-11-01

    The purpose of this investigation was to describe the clinical spectrum of invasive Fusobacterium necrophorum infections and Lemièrre's syndrome, to examine the role of underlying thrombophilia and concomitant mononucleosis in Lemièrre's syndrome, and to describe thromboembolic complications. Patients with invasive F. necrophorum infections were identified either prospectively or retrospectively through the regional database of clinical microbiology from 2000 to 2015. Patient records were reviewed and blood samples from patients with Lemièrre's syndrome were collected for Epstein-Barr virus (EBV) serology and screening for thrombophilia. Of the 65 patients included, 33 had Lemièrre's syndrome. Of the remaining 32 patients, other infections of the respiratory tract and abdominal or urogenital infections were most common. Patients with Lemièrre's syndrome or other tonsillar infections were younger than patients from the other groups. For Lemièrre's syndrome, the 26 patients with severe sepsis on admittance had longer duration of symptoms. Three of five patients who developed distant manifestations had more than 14 days of symptoms. Jugular vein thrombosis was verified in 14 patients, two of whom developed serious complications. Three of 26 patients tested had factor V Leiden mutation, corresponding to the background prevalence. One of 22 patients tested had a concomitant EBV infection. This study confirms earlier studies of the clinical spectrum caused by F. necrophorum. For Lemièrre's syndrome, the study adds to the knowledge on thromboembolic outcome, demonstrating that jugular vein thrombosis may cause severe complications. The time to treatment seems to be important for the risk of severe disease. In this study, concomitant EBV infection or underlying thrombophilia was uncommon. PMID:26272176

  4. Invasive Fusobacterium necrophorum infections and Lemièrre's syndrome: the role of thrombophilia and EBV.

    PubMed

    Holm, K; Svensson, P J; Rasmussen, M

    2015-11-01

    The purpose of this investigation was to describe the clinical spectrum of invasive Fusobacterium necrophorum infections and Lemièrre's syndrome, to examine the role of underlying thrombophilia and concomitant mononucleosis in Lemièrre's syndrome, and to describe thromboembolic complications. Patients with invasive F. necrophorum infections were identified either prospectively or retrospectively through the regional database of clinical microbiology from 2000 to 2015. Patient records were reviewed and blood samples from patients with Lemièrre's syndrome were collected for Epstein-Barr virus (EBV) serology and screening for thrombophilia. Of the 65 patients included, 33 had Lemièrre's syndrome. Of the remaining 32 patients, other infections of the respiratory tract and abdominal or urogenital infections were most common. Patients with Lemièrre's syndrome or other tonsillar infections were younger than patients from the other groups. For Lemièrre's syndrome, the 26 patients with severe sepsis on admittance had longer duration of symptoms. Three of five patients who developed distant manifestations had more than 14 days of symptoms. Jugular vein thrombosis was verified in 14 patients, two of whom developed serious complications. Three of 26 patients tested had factor V Leiden mutation, corresponding to the background prevalence. One of 22 patients tested had a concomitant EBV infection. This study confirms earlier studies of the clinical spectrum caused by F. necrophorum. For Lemièrre's syndrome, the study adds to the knowledge on thromboembolic outcome, demonstrating that jugular vein thrombosis may cause severe complications. The time to treatment seems to be important for the risk of severe disease. In this study, concomitant EBV infection or underlying thrombophilia was uncommon.

  5. Methylation of Epstein-Barr virus Rta promoter in EBV primary infection, reactivation and lymphoproliferation.

    PubMed

    Germi, Raphaële; Guigue, Nicolas; Lupo, Julien; Semenova, Touyana; Grossi, Laurence; Vermeulen, Odile; Epaulard, Olivier; de Fraipont, Florence; Morand, Patrice

    2016-10-01

    During Epstein-Barr virus (EBV) latency, the EBV genome is largely silenced by methylation. This silencing is overturned during the switch to the lytic cycle. A key event is the production of the viral protein Zta which binds to three Zta-response elements (ZRE) from the Rta promoter (Rp), two of which (ZRE2 and ZRE3) include three CpG motifs methylated in the latent genome. The bisulphite pyrosequencing reaction was used to quantify the methylation of ZRE2, ZRE3a, and ZRE3b in EBV-positive cell lines and in ex vivo samples of EBV-related diseases, in order to assess whether the level of methylation in these ZREs could provide additional information to viral DNA load and serology in the characterization of EBV-associated diseases. In PBMC from two patients with infectious mononucleosis, over time Rp became increasingly methylated whereas EBV load decreased. In tonsil from patients with chronic tonsillitis, the methylation was less than in EBV-associated tumors, regardless of the viral load. This was even more striking when only the ZRE3a and ZRE3b were considered since some samples presented unbalanced profiles on ZRE2. EBV reactivation in cell culture showed that the reduction in the overall level of methylation was closely related to the production of unmethylated virions. Thus, an assessment of the level of methylation may help to better characterize EBV replication in PBMC and in biopsies with high EBV load, during infectious mononucleosis and EBV-associated cancers. J. Med. Virol. 88:1814-1820, 2016. © 2016 Wiley Periodicals, Inc. PMID:26990870

  6. The Epstein-Barr virus (EBV) early protein EB2 is a posttranscriptional activator expressed under the control of EBV transcription factors EB1 and R.

    PubMed Central

    Buisson, M; Manet, E; Trescol-Biemont, M C; Gruffat, H; Durand, B; Sergeant, A

    1989-01-01

    From the cloning and characterization of cDNAs, we found that the Epstein-Barr virus (EBV) open reading frame (ORF) BMLF1-BSLF2 coding for the early protein EB2 is present in several mRNAs generated by alternative splicing and expressed in the leftward direction from two promoters PM and PM1. The PM promoter controls the expression of two abundant mRNA species of 1.9 and 2 kilobases (kb), whereas the PM1 promoter controls the expression of at least three mRNAs 3.6, 4.0, and 4.4 kb long. The PM promoter probably overlaps with the PS promoter which controls the transcription of a 3.6-kb mRNA expressed in the rightward direction and containing the ORF BSRF1. Although it increases the amount of chloramphenicol acetyltransferase enzyme expressed from the chimeric pMCAT gene, EB2 is not a promiscuous trans-activator of gene expression and does not positively regulate its own expression from promoter PM. The EB2 activation is not promoter dependent but could possibly act by stabilizing mRNAs and increasing their translation. The PM promoter is, however, activated by the two EBV transcription trans-acting factors, EB1 and R, encoded by the EBV ORFs BZLF1 and BRLF1, respectively. EB1 activates the PM promoter from a consensus AP-1 binding site, and R activates the PM promoter from an enhancer. Images PMID:2555554

  7. An Epstein-Barr Virus Encoded Inhibitor of Colony Stimulating Factor-1 Signaling Is an Important Determinant for Acute and Persistent EBV Infection

    PubMed Central

    Ohashi, Makoto; Fogg, Mark H.; Orlova, Nina; Quink, Carol; Wang, Fred

    2012-01-01

    Acute Epstein-Barr virus (EBV) infection is the most common cause of Infectious Mononucleosis. Nearly all adult humans harbor life-long, persistent EBV infection which can lead to development of cancers including Hodgkin Lymphoma, Burkitt Lymphoma, nasopharyngeal carcinoma, gastric carcinoma, and lymphomas in immunosuppressed patients. BARF1 is an EBV replication-associated, secreted protein that blocks Colony Stimulating Factor 1 (CSF-1) signaling, an innate immunity pathway not targeted by any other virus species. To evaluate effects of BARF1 in acute and persistent infection, we mutated the BARF1 homologue in the EBV-related herpesvirus, or lymphocryptovirus (LCV), naturally infecting rhesus macaques to create a recombinant rhLCV incapable of blocking CSF-1 (ΔrhBARF1). Rhesus macaques orally challenged with ΔrhBARF1 had decreased viral load indicating that CSF-1 is important for acute virus infection. Surprisingly, ΔrhBARF1 was also associated with dramatically lower virus setpoints during persistent infection. Normal acute viral load and normal viral setpoints during persistent rhLCV infection could be restored by Simian/Human Immunodeficiency Virus-induced immunosuppression prior to oral inoculation with ΔrhBARF1 or infection of immunocompetent animals with a recombinant rhLCV where the rhBARF1 was repaired. These results indicate that BARF1 blockade of CSF-1 signaling is an important immune evasion strategy for efficient acute EBV infection and a significant determinant for virus setpoint during persistent EBV infection. PMID:23300447

  8. Src kinase and Syk activation initiate PI3K signaling by a chimeric latent membrane protein 1 in Epstein-Barr virus (EBV)+ B cell lymphomas.

    PubMed

    Hatton, Olivia; Lambert, Stacie L; Krams, Sheri M; Martinez, Olivia M

    2012-01-01

    The B lymphotrophic γ-herpesvirus EBV is associated with a variety of lymphoid- and epithelial-derived malignancies, including B cell lymphomas in immunocompromised and immunosuppressed individuals. The primary oncogene of EBV, latent membrane protein 1 (LMP1), activates the PI3K/Akt pathway to induce the autocrine growth factor, IL-10, in EBV-infected B cells, but the mechanisms underlying PI3K activation remain incompletely understood. Using small molecule inhibition and siRNA strategies in human B cell lines expressing a chimeric, signaling-inducible LMP1 protein, nerve growth factor receptor (NGFR)-LMP1, we show that NGFR-LMP1 utilizes Syk to activate PI3K/Akt signaling and induce IL-10 production. NGFR-LMP1 signaling induces phosphorylation of BLNK, a marker of Syk activation. Whereas Src kinases are often required for Syk activation, we show here that PI3K/Akt activation and autocrine IL-10 production by NGFR-LMP1 involves the Src family kinase Fyn. Finally, we demonstrate that NGFR-LMP1 induces phosphorylation of c-Cbl in a Syk- and Fyn-dependent fashion. Our results indicate that the EBV protein LMP1, which lacks the canonical ITAM required for Syk activation, can nevertheless activate Syk, and the Src kinase Fyn, resulting in downstream c-Cbl and PI3K/Akt activation. Fyn, Syk, and PI3K/Akt antagonists thus may present potential new therapeutic strategies that target the oncogene LMP1 for treatment of EBV+ B cell lymphomas.

  9. Primary bilateral adrenal B-cell lymphoma associated with EBV and JCV infection

    PubMed Central

    Barzon, Luisa; Trevisan, Marta; Marino, Filippo; Guzzardo, Vincenza; Palù, Giorgio

    2009-01-01

    Primary lymphoma of the adrenal gland is a rare and highly aggressive disease, with only a few reports in the literature. The pathogenesis is unknown, but detection of Epstein Barr virus (EBV) genome sequences and gene expression in some cases of primary adrenal lymphomas suggested the virus might be a causative agent of the malignancy. While investigating the presence of genome sequences of oncogenic viruses in a large series of adrenal tumors, both EBV and JC polyomavirus (JCV) DNA sequences were detected in a diffuse large primary bilateral B-cell non-Hodgkin lymphoma of the adrenal gland, which was diagnosed only at postmortem examination in a 77 year-old woman with incidentally discovered adrenal masses and primary adrenal insufficiency. The presence of both EBV and JCV genome sequences suggests the relevance of EBV and JCV coinfection in the pathogenesis of this rare form of B-cell lymphoma. PMID:19146683

  10. Stable transfection of Epstein-Barr virus (EBV) nuclear antigen 2 in lymphoma cells containing the EBV P3HR1 genome induces expression of B-cell activation molecules CD21 and CD23.

    PubMed Central

    Cordier, M; Calender, A; Billaud, M; Zimber, U; Rousselet, G; Pavlish, O; Banchereau, J; Tursz, T; Bornkamm, G; Lenoir, G M

    1990-01-01

    A set of B-cell activation molecules, including the Epstein-Barr virus (EBV) receptor CR2 (CD21) and the B-cell activation antigen CD23 (Blast2/Fc epsilon RII), is turned on by infecting EBV-negative B-lymphoma cell lines with immortalizing strains of the viruslike B95-8 (BL/B95 cells). This up regulation may represent one of the mechanisms involved in EBV-mediated B-cell immortalization. The P3HR1 nonimmortalizing strain of the virus, which is deleted for the entire Epstein-Barr nuclear antigen 2 (EBNA2) protein open reading frame, is incapable of inducing the expression of CR2 and CD23, suggesting a crucial role for EBNA2 in the activation of these molecules. In addition, lymphoma cells containing the P3HR1 genome (BL/P3HR1 cells) do not express the viral latent membrane protein (LMP), which is regularly expressed in cells infected with immortalizing viral strains. Using electroporation, we have transfected the EBNA2 gene cloned in an episomal vector into BL/P3HR1 cells and have obtained cell clones that stably express the EBNA2 protein. In these clones, EBNA2 expression was associated with an increased amount of CR2 and CD23 steady-state RNAs. Of the three species of CD23 mRNAs described, the Fc epsilon RIIa species was preferentially expressed in these EBNA2-expressing clones. An increased cell surface expression of CR2 but not of CD23 was observed, and the soluble form of CD23 molecule (SCD23) was released. We were, however, not able to detect any expression of LMP in these cell clones. These data demonstrate that EBNA2 gene is able to complement P3HR1 virus latent functions to induce the activation of CR2 and CD23 expression, and they emphasize the role of EBNA2 protein in the modulation of cellular gene implicated in B-cell proliferation and hence in EBV-mediated B-cell immortalization. Nevertheless, EBNA2 expression in BL/P3HR1 cells is not able to restore the level of CR2 and CD23 expression observed in BL/B95 cells, suggesting that other cellular or viral

  11. Detection and quantification of Epstein-Barr virus EBER1 in EBV-infected cells by fluorescent in situ hybridization and flow cytometry

    NASA Technical Reports Server (NTRS)

    Stowe, R. P.; Cubbage, M. L.; Sams, C. F.; Pierson, D. L.; Barrett, A. D.

    1998-01-01

    A rapid and highly sensitive fluorescent in situ hybridization (FISH) assay was developed to detect Epstein Barr virus (EBV)-infected cells in peripheral blood. Multiple fluorescein-labeled antisense oligonucleotide probes were designed to hybridize to the EBER1 transcript, which is highly expressed in latently infected cells. After a rapid (30 min) hybridization, the cells were analyzed by flow cytometry. EBER1 was detected in several positive control cell lines that have variable numbers of EBV genome copies. No EBER1 was detected in two known EBV-negative cell lines. Northern blot analyses confirmed the presence and quantity of EBER1 transcripts in each cell line. This method was used to quantify the number of EBV-infected cells in peripheral blood from a patient with chronic mononucleosis. These results indicate that EBV-infected cells can be detected at the single cell level, and that this assay can be used to quantify the number of EBV-infected cells in clinical samples.

  12. Inhibition of autophagy in EBV-positive Burkitt's lymphoma cells enhances EBV lytic genes expression and replication

    PubMed Central

    De Leo, A; Colavita, F; Ciccosanti, F; Fimia, G M; Lieberman, P M; Mattia, E

    2015-01-01

    Autophagy, an important degradation system involved in maintaining cellular homeostasis, serves also to eliminate pathogens and process their fragments for presentation to the immune system. Several viruses have been shown to interact with the host autophagic machinery to suppress or make use of this cellular catabolic pathway to enhance their survival and replication. Epstein Barr virus (EBV) is a γ-herpes virus associated with a number of malignancies of epithelial and lymphoid origin in which establishes a predominantly latent infection. Latent EBV can periodically reactivate to produce infectious particles that allow the virus to spread and can lead to the death of the infected cell. In this study, we analyzed the relationship between autophagy and EBV reactivation in Burkitt's lymphoma cells. By monitoring autophagy markers and EBV lytic genes expression, we demonstrate that autophagy is enhanced in the early phases of EBV lytic activation but decreases thereafter concomitantly with increased levels of EBV lytic proteins. In a cell line defective for late antigens expression, we found an inverse correlation between EBV early antigens expression and autophagosomes formation, suggesting that early after activation, the virus is able to suppress autophagy. We report here for the first time that inhibition of autophagy by Bafilomycin A1 or shRNA knockdown of Beclin1 gene, highly incremented EBV lytic genes expression as well as intracellular viral DNA and viral progeny yield. Taken together, these findings indicate that EBV activation induces the autophagic response, which is soon inhibited by the expression of EBV early lytic products. Moreover, our findings open the possibility that pharmacological inhibitors of autophagy may be used to enhance oncolytic viral therapy of EBV-related lymphomas. PMID:26335716

  13. EBV Persistence--Introducing the Virus.

    PubMed

    Thorley-Lawson, David A

    2015-01-01

    Persistent infection by EBV is explained by the germinal center model (GCM) which provides a satisfying and currently the only explanation for EBVs disparate biology. Since the GCM touches on every aspect of the virus, this chapter will serve as an introduction to the subsequent chapters. EBV is B lymphotropic, and its biology closely follows that of normal mature B lymphocytes. The virus persists quiescently in resting memory B cells for the lifetime of the host in a non-pathogenic state that is also invisible to the immune response. To access this compartment, the virus infects naïve B cells in the lymphoepithelium of the tonsils and activates these cells using the growth transcription program. These cells migrate to the GC where they switch to a more limited transcription program, the default program, which helps rescue them into the memory compartment where the virus persists. For egress, the infected memory cells return to the lymphoepithelium where they occasionally differentiate into plasma cells activating viral replication. The released virus can either infect more naïve B cells or be amplified in the epithelium for shedding. This cycle of infection and the quiescent state in memory B cells allow for lifetime persistence at a very low level that is remarkably stable over time. Mathematically, this is a stable fixed point where the mechanisms regulating persistence drive the state back to equilibrium when perturbed. This is the GCM of EBV persistence. Other possible sites and mechanisms of persistence will also be discussed. PMID:26424647

  14. Dithiocarbamates and Viral IL-10 Collaborate in the Immortalization and Evasion of Immune Response in EBV-infected Human B Lymphocytes

    PubMed Central

    Irons, Richard D.; Le, Anh Tuan

    2008-01-01

    Epstein-Barr Virus (EBV) is implicated in the development of a number of human malignancies including several subtypes of non-Hodgkin lymphoma (NHL) [1]. Lymphoproliferative disease and NHL occurring in severely immunosuppressed individuals almost all involve EBV and have been extensively studied and modeled in vitro. EBV has also been causally associated with some cases of NHL occurring in otherwise immunocompetent individuals. However, a direct role for EBV in the pathogenesis of neoplasms developing in the presence of an otherwise competent immune system has not been established. We investigated potential interactions between dithiocarbamates (DTC), an important class of thiono-sulfur compounds, and EBV leading to immortalization of human B lymphocytes and evasion of cell-mediated immune response in culture. Primary lymphocyte cultures employing wild-type and recombinant EBV mutants were used to assess the respective roles of DTC and viral genes in lymphocyte transformation and survival. Pretreatment of EBV-infected human B lymphocytes with DTC directly enhanced transformation in the absence of T cells (5 nM) and independently increased survival of transformed cells in the presence of competent autologous T cells (10 nM). Both DTC-induced transformation and immortalization of EBV-infected B lymphocytes were dependent on the expression of viral IL-10. These results provide a biological basis for studying collaborations between chemical and virus that alter lymphocyte biology, and provide a rationale for further molecular epidemiology studies to better understand the potential influence of these interactions on the development of NHL and perhaps other viral-associated malignancies. PMID:18163983

  15. 5-hydroxymethylation of the EBV genome regulates the latent to lytic switch

    PubMed Central

    Wille, Coral K.; Nawandar, Dhananjay M.; Henning, Amanda N.; Ma, Shidong; Oetting, Kayla M.; Lee, Dennis; Lambert, Paul; Johannsen, Eric C.; Kenney, Shannon C.

    2015-01-01

    Latent Epstein–Barr virus (EBV) infection and cellular hypermethylation are hallmarks of undifferentiated nasopharyngeal carcinoma (NPC). However, EBV infection of normal oral epithelial cells is confined to differentiated cells and is lytic. Here we demonstrate that the EBV genome can become 5-hydroxymethylated and that this DNA modification affects EBV lytic reactivation. We show that global 5-hydroxymethylcytosine (5hmC)-modified DNA accumulates during normal epithelial-cell differentiation, whereas EBV+ NPCs have little if any 5hmC-modified DNA. Furthermore, we find that increasing cellular ten–eleven translocation (TET) activity [which converts methylated cytosine (5mC) to 5hmC] decreases methylation, and increases 5hmC modification, of lytic EBV promoters in EBV-infected cell lines containing highly methylated viral genomes. Conversely, inhibition of endogenous TET activity increases lytic EBV promoter methylation in an EBV-infected telomerase-immortalized normal oral keratinocyte (NOKs) cell line where lytic viral promoters are largely unmethylated. We demonstrate that these cytosine modifications differentially affect the ability of the two EBV immediate-early proteins, BZLF1 (Z) and BRLF1 (R), to induce the lytic form of viral infection. Although methylation of lytic EBV promoters increases Z-mediated and inhibits R-mediated lytic reactivation, 5hmC modification of lytic EBV promoters has the opposite effect. We also identify a specific CpG-containing Z-binding site on the BRLF1 promoter that must be methylated for Z-mediated viral reactivation and show that TET-mediated 5hmC modification of this site in NOKs prevents Z-mediated viral reactivation. Decreased 5-hydroxymethylation of cellular and viral genes may contribute to NPC formation. PMID:26663912

  16. [Lifecycles of EBV and cancer].

    PubMed

    Murata, Takayuki

    2014-01-01

    Epstein-Barr virus (EBV) is a member of gamma-herpesvirus, which can cause various types of tumor. Coexisting with the host for a long period of time, it has evolved unique and sophisticated strategy for survival by taking complicated, tactical modes of infection. Such modes include latent and lytic infections, and latent state is further categorized into four types. Differences and transitions in such lifestyles are significantly associated not only with virus amplification, but also with pathology and advancement of the disorders. I here review oncogenesis and pathogenesis of EBV-related disorders, especially focusing on our recent results on the modes of EBV infection. PMID:25765985

  17. Differences in Epstein-Barr virus (EBV) receptors expression on various human lymphoid targets and their significance to EBV-cell interaction.

    PubMed

    Stocco, R; Sauvageau, G; Menezes, J

    1988-10-01

    This study was aimed at quantitating, by means of fluorescence-activated cell sorter (FACS), EBV binding to different types of target cells, and at learning about a possible relation between EBV receptor density and the fate of cell-surface bound virus. We used fluoresceinated virus preparations of two strains of EBV (B95-8: lymphocyte transforming strain; P3HR-1: non-transforming strain) to analyze quantitatively the expression and density of EBV receptors on different human lymphoid cell lines and on B lymphocytes from both EBV-seropositive and -seronegative donors. FACS analysis was also used as a tool to approximate the cell surface area of the different lymphoid cells examined. Our results indicate that: (a) after accounting for the difference in cell surface dimensios, the fluorescence intensity of EBV-bound Raji (a B line) cells was three to four times higher per unit area than that of EBV-bound fresh B lymphocytes from an EBV-seropositive donor; (b) Molt-4 (a T line) cells bound about 21-fold less P3HR-1 EBV and 6-fold less B95-8 EBV than Raji cells per unit area; (c) B lymphocytes from EBV-seronegative adult donors bound only about one third as much virus as B cells from seropositive individuals; (d) two B lymphocyte sub-populations can be identified in the peripheral blood in regard to their ability to bind EBV, regardless of the EBV antibody status of the donor; (e) the EBV receptor on Molt-4 cells appears structurally different from the one found on Raji cells since EBV binding to Molt-4 cells was not blocked by a monoclonal antibody (OKB7) specific to the complement receptor (CR2). Further, in contrast to Raji cells, Molt-4 expressed a differential binding activity for each of the two EBV strains used. Taken together, the important differences observed in regard to EBV attachment to various targets also appear to relate to the fate of cell-surface bound virus: i.e., virus penetration might be determined, at least in part, by the density of EBV

  18. High Epstein-Barr virus serum load and elevated titers of anti-ZEBRA antibodies in patients with EBV-harboring tumor cells of Hodgkin's disease.

    PubMed

    Drouet, E; Brousset, P; Fares, F; Icart, J; Verniol, C; Meggetto, F; Schlaifer, D; Desmorat-Coat, H; Rigal-Huguet, F; Niveleau, A; Delsol, G

    1999-04-01

    Hodgkin's disease is commonly associated with EBV latent infection. The incidence of EBV reactivation (active infection or EBV infection with replicative cycle) was evaluated in a series of 30 patients with untreated Hodgkin's disease (except for one case with chronic lymphocytic leukemia) by quantitation of EBV DNA and titration of anti-ZEBRA antibodies in serum samples. DNA was detected in serum (>2.5 x 10(2) genomes/ml) in 15 of 30 patients and was more frequent in Hodgkin's disease with EBV-positive Reed-Sternberg cells (10/12) than in EBV-negative cases (5/18), (P< 0.01). Of interest was the demonstration that viremia correlated well with increased titers of anti-ZEBRA IgG and/or standard serological profiles of EBV reactivation (12/15), (P < 0.05). However the lack of EBV replicative cycle in Reed-Sternberg cells (negative for ZEBRA antigen and early antigen BHLF1) suggests that the viral replication occurs in a nonneoplastic cell compartment rather than in tumor cells. The measurement of EBV DNA loads and the titration of anti-ZEBRA antibodies shed new lights on the link between activation of EBV replication and Hodgkin's disease: these serological markers together with the determination of the EBV status of the tumor suggest that replication of the viral genome occurs with a decreased efficiency of the immune system, thus allowing progression of the tumor.

  19. Alice in Wonderland syndrome as a presenting symptom of EBV infection.

    PubMed

    Liaw, S B; Shen, E Y

    1991-01-01

    Four Chinese patients (2 boys, 2 girls), ages 4-9 years, who had episodes of perception error of body schema and objects are reported. The metamorphopsia, which had been named Alice in Wonderland syndrome, is the major presentation. All of them were proved to have acute Epstein-Barr virus infection, as documented by positive heterophil antibody test and/or positive IgM antibody to Epstein-Barr virus capsid antigen. The duration of the perception disorder ranged from 1 week to 3 months. We believe that any young child presenting with Alice in Wonderland syndrome should undergo examination for Epstein-Barr virus infection; complete recovery from the disorder can be expected. PMID:1665694

  20. Epstein-Barr virus DNA loads in adult human immunodeficiency virus type 1-infected patients receiving highly active antiretroviral therapy

    NASA Technical Reports Server (NTRS)

    Ling, Paul D.; Vilchez, Regis A.; Keitel, Wendy A.; Poston, David G.; Peng, Rong Sheng; White, Zoe S.; Visnegarwala, Fehmida; Lewis, Dorothy E.; Butel, Janet S.

    2003-01-01

    Patients with human immunodeficiency virus type 1 (HIV-1) infection are at high risk of developing Epstein-Barr virus (EBV)-associated lymphoma. However, little is known of the EBV DNA loads in patients receiving highly active antiretroviral therapy (HAART). Using a real-time quantitative polymerase chain reaction assay, we demonstrated that significantly more HIV-1-infected patients receiving HAART than HIV-1-uninfected volunteers had detectable EBV DNA in blood (57 [81%] of 70 vs. 11 [16%] of 68 patients; P=.001) and saliva (55 [79%] of 68 vs. 37 [54%] of 68 patients; P=.002). The mean EBV loads in blood and saliva samples were also higher in HIV-1-infected patients than in HIV-1-uninfected volunteers (P=.001). The frequency of EBV detection in blood was associated with lower CD4+ cell counts (P=.03) among HIV-1-infected individuals, although no differences were observed in the EBV DNA loads in blood or saliva samples in the HIV-1-infected group. Additional studies are needed to determine whether EBV-specific CD4+ and CD8+ cells play a role in the pathogenesis of EBV in HIV-1-infected patients receiving HAART.

  1. Meta-analysis of nasopharyngeal carcinoma microarray data explores mechanism of EBV-regulated neoplastic transformation

    PubMed Central

    Chen, Xia; Liang, Shuang; Zheng, WenLing; Liao, ZhiJun; Shang, Tao; Ma, WenLi

    2008-01-01

    Background Epstein-Barr virus (EBV) presumably plays an important role in the pathogenesis of nasopharyngeal carcinoma (NPC), but the molecular mechanism of EBV-dependent neoplastic transformation is not well understood. The combination of bioinformatics with evidences from biological experiments paved a new way to gain more insights into the molecular mechanism of cancer. Results We profiled gene expression using a meta-analysis approach. Two sets of meta-genes were obtained. Meta-A genes were identified by finding those commonly activated/deactivated upon EBV infection/reactivation. These genes could be key players for pathways de-regulated by EBV during latent infection and lytic proliferation. Meta-B genes were obtained from differential genes commonly expressed in NPC and PEL (primary effusion lymphoma). We then integrated meta-A, meta-B and associated factors into an interaction network using acquired information. Our analysis suggests that NPC transformation depends on timely regulation of DEK, CDK inhibitor(s), p53, RB and several transcriptional cascades, interconnected by E2F, AP-1, NF-κB, STAT3 among others during latent and lytic cycles. Conclusion In conclusion, our meta-analysis strategy re-analyzed EBV-related tumor data sets and identified sets of meta-genes possibly involved in maintaining latent or switching to lytic cycles of EBV in NPC. The results of this analysis may shed new lights to further our understanding of the EBV-led neoplastic transformation. PMID:18605998

  2. Nonmuscle myosin heavy chain IIA mediates Epstein–Barr virus infection of nasopharyngeal epithelial cells

    PubMed Central

    Xiong, Dan; Du, Yong; Wang, Hong-Bo; Zhao, Bo; Zhang, Hua; Li, Yan; Hu, Li-Juan; Cao, Jing-Yan; Zhong, Qian; Liu, Wan-Li; Li, Man-Zhi; Zhu, Xiao-Feng; Tsao, Sai Wah; Hutt-Fletcher, Lindsey M.; Song, Erwei; Zeng, Yi-Xin; Kieff, Elliott; Zeng, Mu-Sheng

    2015-01-01

    EBV causes B lymphomas and undifferentiated nasopharyngeal carcinoma (NPC). Although the mechanisms by which EBV infects B lymphocytes have been extensively studied, investigation of the mechanisms by which EBV infects nasopharyngeal epithelial cells (NPECs) has only recently been enabled by the successful growth of B lymphoma Mo-MLV insertion region 1 homolog (BMI1)-immortalized NPECs in vitro and the discovery that neuropilin 1 expression positively affects EBV glycoprotein B (gB)-mediated infection and tyrosine kinase activations in enhancing EBV infection of BMI1-immortalized NPECs. We have now found that even though EBV infected NPECs grown as a monolayer at extremely low efficiency (<3%), close to 30% of NPECs grown as sphere-like cells (SLCs) were infected by EBV. We also identified nonmuscle myosin heavy chain IIA (NMHC-IIA) as another NPEC protein important for efficient EBV infection. EBV gH/gL specifically interacted with NMHC-IIA both in vitro and in vivo. NMHC-IIA densely aggregated on the surface of NPEC SLCs and colocalized with EBV. EBV infection of NPEC SLCs was significantly reduced by NMHC-IIA siRNA knock-down. NMHC-IIA antisera also efficiently blocked EBV infection. These data indicate that NMHC-IIA is an important factor for EBV NPEC infection. PMID:26290577

  3. Nonmuscle myosin heavy chain IIA mediates Epstein-Barr virus infection of nasopharyngeal epithelial cells.

    PubMed

    Xiong, Dan; Du, Yong; Wang, Hong-Bo; Zhao, Bo; Zhang, Hua; Li, Yan; Hu, Li-Juan; Cao, Jing-Yan; Zhong, Qian; Liu, Wan-Li; Li, Man-Zhi; Zhu, Xiao-Feng; Tsao, Sai Wah; Hutt-Fletcher, Lindsey M; Song, Erwei; Zeng, Yi-Xin; Kieff, Elliott; Zeng, Mu-Sheng

    2015-09-01

    EBV causes B lymphomas and undifferentiated nasopharyngeal carcinoma (NPC). Although the mechanisms by which EBV infects B lymphocytes have been extensively studied, investigation of the mechanisms by which EBV infects nasopharyngeal epithelial cells (NPECs) has only recently been enabled by the successful growth of B lymphoma Mo-MLV insertion region 1 homolog (BMI1)-immortalized NPECs in vitro and the discovery that neuropilin 1 expression positively affects EBV glycoprotein B (gB)-mediated infection and tyrosine kinase activations in enhancing EBV infection of BMI1-immortalized NPECs. We have now found that even though EBV infected NPECs grown as a monolayer at extremely low efficiency (<3%), close to 30% of NPECs grown as sphere-like cells (SLCs) were infected by EBV. We also identified nonmuscle myosin heavy chain IIA (NMHC-IIA) as another NPEC protein important for efficient EBV infection. EBV gH/gL specifically interacted with NMHC-IIA both in vitro and in vivo. NMHC-IIA densely aggregated on the surface of NPEC SLCs and colocalized with EBV. EBV infection of NPEC SLCs was significantly reduced by NMHC-IIA siRNA knock-down. NMHC-IIA antisera also efficiently blocked EBV infection. These data indicate that NMHC-IIA is an important factor for EBV NPEC infection. PMID:26290577

  4. Chronic active Epstein-Barr virus infection with marked pericardial effusion successfully treated with allogeneic peripheral blood stem cell transplantation.

    PubMed

    Matsui, Shinichiro; Takeda, Yusuke; Isshiki, Yusuke; Yamazaki, Atsuko; Nakao, Sanshiro; Takaishi, Koji; Nagao, Yuhei; Hasegawa, Nagisa; Togasaki, Emi; Shimizu, Ryoh; Kawajiri, Chika; Sakai, Shio; Mimura, Naoya; Takeuchi, Masahiro; Ohwada, Chikako; Sakaida, Emiko; Iseki, Tohru; Imadome, Ken-Ichi; Nakaseko, Chiaki

    2016-05-01

    A 23-year-old woman presented with a persistent fever and shortness of breath. Computed tomography showed marked pericardial effusion, hepatosplenomegaly, and cervical and mediastinal lymph node swelling. Epstein-Barr virus (EBV) antibody titers were abnormally elevated, and the copy number of EBV-DNA was increased in peripheral blood. Based on these observations, she was diagnosed with chronic active EBV infection (CAEBV). The EBV-infected cells in her peripheral blood were CD4(+)T lymphocytes. Fever and pericardial effusion improved following treatment with a combination of prednisolone, etoposide, and cyclosporine; however, peripheral blood EBV-DNA levels remained high. The patient underwent allogeneic peripheral blood stem cell transplantation from an EBV-seronegative, HLA-matched sibling donor, with fludarabine and melphalan conditioning. The post-transplantation course was uneventful, except for mild skin acute graft-versus-host disease (grade 2). EBV-DNA became undetectable in peripheral blood 98 days post transplantation. She has since been in good health without disease recurrence. CAEBV is a potentially fatal disease caused by persistent EBV infection of T lymphocytes or natural killer cells, thus requiring prompt treatment and allogeneic transplantation. Pericardial effusion is rarely observed in CAEBV and can impede its diagnosis. Therefore, we should be aware that patients may present with marked pericardial effusion as an initial manifestation of CAEBV. PMID:27263789

  5. A novel mouse xenotransplantation model of EBV-T/NK-LPD and the application of the mouse model.

    PubMed

    Imadome, Ken-Ichi

    2013-01-01

    Chronic active Epstein-Barr virus (EBV) infection (CAEBV), characterized by proliferation of EBV-infected T or NK cells, is a disease of unknown pathogenesis and requires hematopoietic stem cell transplantation for curative treatment. Here we show that intravenous injection of peripheral blood mononuclear cells (PBMCs) isolated from patients with CAEBV to NOD/Shi-scid/IL-2R γ(null) (NOG) mice leads to engraftment of EBV-infected T or NK cells. Analysis of TCR repertoire identified an identical predominant EBV-infected T-cell clone both in a patient and a mouse transplanted with his PBMCs. EBV-infected T or NK cells infiltrated to most major organs including the liver, spleen, lungs, kidneys, adrenal glands, and intestine, showing histological characteristics of CAEBV. Expression of EBNA1, LMP1, and LMP2A, but not EBNA2, in these cells indicated the latency II program of EBV gene characteristic to CAEBV. High levels of TNF-α, IFN-γ, and RANTES were detected in the peripheral blood of these mice. EBV-containing fractions of either CD8(+), γδT, or NK cell lineages failed to engraft, once they were isolated from PBMCs ; they could engraft only when CD4(+) cell fraction was transplanted in parallel. Isolated EBV-containing CD4(+) T cells, in contrast, did engraft on their own. This is the first report of an animal model of CAEBV and suggest that EBV-infected T or NK cells in CAEBV are not truly neoplastic but are dependent on CD4(+) T cells for their proliferation in vivo. PMID:24390103

  6. Identification of Novel Small Organic Compounds with Diverse Structures for the Induction of Epstein-Barr Virus (EBV) Lytic Cycle in EBV-Positive Epithelial Malignancies

    PubMed Central

    Choi, Chung King; Ho, Dona N.; Hui, Kwai Fung; Kao, Richard Y.; Chiang, Alan K. S.

    2015-01-01

    Phorbol esters, which are protein kinase C (PKC) activators, and histone deacetylase (HDAC) inhibitors, which cause enhanced acetylation of cellular proteins, are the main classes of chemical inducers of Epstein-Barr virus (EBV) lytic cycle in latently EBV-infected cells acting through the PKC pathway. Chemical inducers which induce EBV lytic cycle through alternative cellular pathways may aid in defining the mechanisms leading to lytic cycle reactivation and improve cells’ responsiveness towards lytic induction. We performed a phenotypic screening on a chemical library of 50,240 novel small organic compounds to identify novel class(es) of strong inducer(s) of EBV lytic cycle in gastric carcinoma (GC) and nasopharyngeal carcinoma (NPC) cells. Five hit compounds were selected after three successive rounds of increasingly stringent screening. All five compounds are structurally diverse from each other and distinct from phorbol esters or HDAC inhibitors. They neither cause hyperacetylation of histone proteins nor significant PKC activation at their working concentrations, suggesting that their biological mode of action are distinct from that of the known chemical inducers. Two of the five compounds with rapid lytic-inducing action were further studied for their mechanisms of induction of EBV lytic cycle. Unlike HDAC inhibitors, lytic induction by both compounds was not inhibited by rottlerin, a specific inhibitor of PKCδ. Interestingly, both compounds could cooperate with HDAC inhibitors to enhance EBV lytic cycle induction in EBV-positive epithelial cancer cells, paving way for the development of strategies to increase cells’ responsiveness towards lytic reactivation. One of the two compounds bears structural resemblance to iron chelators and the other strongly activates the MAPK pathways. These structurally diverse novel organic compounds may represent potential new classes of chemicals that can be used to investigate any alternative mechanism(s) leading to EBV

  7. Identification of Novel Small Organic Compounds with Diverse Structures for the Induction of Epstein-Barr Virus (EBV) Lytic Cycle in EBV-Positive Epithelial Malignancies.

    PubMed

    Choi, Chung King; Ho, Dona N; Hui, Kwai Fung; Kao, Richard Y; Chiang, Alan K S

    2015-01-01

    Phorbol esters, which are protein kinase C (PKC) activators, and histone deacetylase (HDAC) inhibitors, which cause enhanced acetylation of cellular proteins, are the main classes of chemical inducers of Epstein-Barr virus (EBV) lytic cycle in latently EBV-infected cells acting through the PKC pathway. Chemical inducers which induce EBV lytic cycle through alternative cellular pathways may aid in defining the mechanisms leading to lytic cycle reactivation and improve cells' responsiveness towards lytic induction. We performed a phenotypic screening on a chemical library of 50,240 novel small organic compounds to identify novel class(es) of strong inducer(s) of EBV lytic cycle in gastric carcinoma (GC) and nasopharyngeal carcinoma (NPC) cells. Five hit compounds were selected after three successive rounds of increasingly stringent screening. All five compounds are structurally diverse from each other and distinct from phorbol esters or HDAC inhibitors. They neither cause hyperacetylation of histone proteins nor significant PKC activation at their working concentrations, suggesting that their biological mode of action are distinct from that of the known chemical inducers. Two of the five compounds with rapid lytic-inducing action were further studied for their mechanisms of induction of EBV lytic cycle. Unlike HDAC inhibitors, lytic induction by both compounds was not inhibited by rottlerin, a specific inhibitor of PKCδ. Interestingly, both compounds could cooperate with HDAC inhibitors to enhance EBV lytic cycle induction in EBV-positive epithelial cancer cells, paving way for the development of strategies to increase cells' responsiveness towards lytic reactivation. One of the two compounds bears structural resemblance to iron chelators and the other strongly activates the MAPK pathways. These structurally diverse novel organic compounds may represent potential new classes of chemicals that can be used to investigate any alternative mechanism(s) leading to EBV

  8. EGCG debilitates the persistence of EBV latency by reducing the DNA binding potency of nuclear antigen 1

    SciTech Connect

    Chen, Ya-Lin; Tsai, Hsing-Lyn; Peng, Chih-Wen

    2012-01-20

    Highlights: Black-Right-Pointing-Pointer Two cell-based reporter platforms were established for screening of EBNA1 inhibitors. Black-Right-Pointing-Pointer EGCG acts as an inhibitor to block EBNA1 binding with the cognate oriP sequence. Black-Right-Pointing-Pointer EGCG debilitates EBNA1-dependent transcription enhancement and episome maintenance. Black-Right-Pointing-Pointer EGCG impairs persistence of EBV latency. Black-Right-Pointing-Pointer EGCG is a potent anti-EBV agent for targeting the latent cascade of EBV. -- Abstract: Because the expression of EBNA1 is prevalent in all EBV-associated tumors, it has become one of the most attractive drug targets for the discovery of anti-EBV compounds. In a cell-based reporter system, EBNA1 consistently upregulated the transcription of an oriP-Luc mini-EBV episome by 6- to 8-fold. The treatment of cells with 50 {mu}M EGCG effectively blocked the binding of EBNA1 to oriP-DNA both in vivo and in vitro, which led to the abrogation of EBNA1-dependent episome maintenance and transcriptional enhancement. Importantly, the anti-EBNA1 effects caused by EGCG ultimately impaired the persistence of EBV latent infection. Our data suggest that the inhibition of EBNA1 activity by EGCG could be a promising starting point for the development of new protocols for anti-EBV therapy.

  9. Detection of EBV, HBV, HCV, HIV-1, HTLV-I and -II, and SMRV in Human and Other Primate Cell Lines

    PubMed Central

    Uphoff, Cord C.; Denkmann, Sabine A.; Steube, Klaus G.; Drexler, Hans G.

    2010-01-01

    The high prevalence of contaminated cell cultures suggests that viral contaminations might be distributed among cultures. We investigated more than 460 primate cell lines for Epstein-Barr (EBV), hepatitis B (HBV), hepatitis C (HCV), human immunodeficiency virus type 1 (HIV-1), human T-cell leukemia/lymphoma virus I and II (HTLV-I/-II), and squirrel monkey retrovirus (SMRV) infections for risk assessment. None of the cell lines were infected with HCV, HIV-1, or HTLV-I/-II. However, one cell line displayed reverse transcriptase activity. Thirty-nine cell lines harbored EBV DNA sequences. Studies on the lytic phase of EBV revealed that five cell lines produce EBV particles and six further cell lines produced EBV upon stimulation. One cell line contained an integrated HBV genome fragment but showed no virus production. Six cell lines were SMRV-infected. Newly established cell lines should be tested for EBV infections to detect B-lymphoblastoid cell lines (B-LCL). B-LCLs established with EBV from cell line B95-8 should be tested for SMRV infections. PMID:20454443

  10. Switching of EBV cycles between latent and lytic states.

    PubMed

    Murata, Takayuki; Tsurumi, Tatsuya

    2014-05-01

    The EBV is a human gamma-herpesvirus that is associated with a variety of neoplasms. Upon primary infection, it transiently runs a short lytic program and then predominantly establishes latent infection. Only a small percentage of infected cells switch from the latent stage into the lytic cycle and produce progeny viruses. Although EBV in cancer cells is mostly in the latent state, the lytic cycle of the virus is also expected to play a pivotal role in development and maintenance of tumors because of its association with secretion of cytokines or growth factors. Moreover, if efficient artificial induction of lytic replication could somehow be achieved, development of oncolytic therapy for EBV-positive cancers would be conceivable. Thus, understanding the switching mechanism is of essential importance. Reactivation of the virus from latency is dependent on expression of the viral BZLF1 protein. The BZLF1 promoter (Zp) normally exhibits only low basal activity but is activated in response to chemical or biological inducers, such as 12-O-tetradecanoylphorbol-13-acetate, calcium ionophore, or histone deacetylase inhibitors. Transcription from the Zp is regulated by the balance between active and suppressive epigenetic histone marks, including histone acetylation, histone H3 Lysine 4 trimethylation and histone H3 lysine 27 trimethylation, being mediated by multiple transcription factors, such as myocyte enhancer factor 2, specificity protein 1, and zinc finger E-box binding homeobox. This review will focus on such molecular mechanisms by which the EBV lytic switch is controlled and discuss the physiological significance of the switching for oncogenesis.

  11. Cross talk between EBV and telomerase: the role of TERT and NOTCH2 in the switch of latent/lytic cycle of the virus.

    PubMed

    Giunco, S; Celeghin, A; Gianesin, K; Dolcetti, R; Indraccolo, S; De Rossi, A

    2015-01-01

    Epstein-Barr virus (EBV)-associated malignancies, as well as lymphoblastoid cell lines (LCLs), obtained in vitro by EBV infection of B cells, express latent viral proteins and maintain their ability to grow indefinitely through inappropriate activation of telomere-specific reverse transcriptase (TERT), the catalytic component of telomerase. Our previous studies demonstrated that high levels of TERT expression in LCLs prevent the activation of EBV lytic cycle, which is instead triggered by TERT silencing. As lytic infection promotes the death of EBV-positive tumor cells, understanding the mechanism(s) by which TERT affects the latent/lytic status of EBV may be important for setting new therapeutic strategies. BATF, a transcription factor activated by NOTCH2, the major NOTCH family member in B cells, negatively affects the expression of BZLF1, the master regulator of viral lytic cycle. We therefore analyzed the interplay between TERT, NOTCH and BATF in LCLs and found that high levels of endogenous TERT are associated with high NOTCH2 and BATF expression levels. In addition, ectopic expression of TERT in LCLs with low levels of endogenous telomerase was associated with upregulation of NOTCH2 and BATF at both mRNA and protein levels. By contrast, infection of LCLs with retroviral vectors expressing functional NOTCH2 did not alter TERT transcript levels. Luciferase reporter assays, demonstrated that TERT significantly activated NOTCH2 promoter in a dose-dependent manner. We also found that NF-κB pathway is involved in TERT-induced NOTCH2 activation. Lastly, pharmacologic inhibition of NOTCH signaling triggers the EBV lytic cycle, leading to the death of EBV-infected cells. Overall, these results indicate that TERT contributes to preserve EBV latency in B cells mainly through the NOTCH2/BAFT pathway, and suggest that NOTCH2 inhibition may represent an appealing therapeutic strategy against EBV-associated malignancies.

  12. KSHV LANA and EBV LMP1 induce the expression of UCH-L1 following viral transformation

    SciTech Connect

    Bentz, Gretchen L.; Bheda-Malge, Anjali; Wang, Ling; Shackelford, Julia; Damania, Blossom; Pagano, Joseph S.

    2014-01-05

    Ubiquitin C-terminal Hydrolase L1 (UCH-L1) has oncogenic properties and is highly expressed during malignancies. We recently documented that Epstein-Barr virus (EBV) infection induces uch-l1 expression. Here we show that Kaposi's Sarcoma-associated herpesvirus (KSHV) infection induced UCH-L1 expression, via cooperation of KSHV Latency-Associated Nuclear Antigen (LANA) and RBP-Jκ and activation of the uch-l1 promoter. UCH-L1 expression was also increased in Primary Effusion Lymphoma (PEL) cells co-infected with KSHV and EBV compared with PEL cells infected only with KSHV, suggesting EBV augments the effect of LANA on uch-l1. EBV latent membrane protein 1 (LMP1) is one of the few EBV products expressed in PEL cells. Results showed that LMP1 was sufficient to induce uch-l1 expression, and co-expression of LMP1 and LANA had an additive effect on uch-l1 expression. These results indicate that viral latency products of both human γ-herpesviruses contribute to uch-l1 expression, which may contribute to the progression of lymphoid malignancies. - Highlights: • Infection of endothelial cells with KSHV induced UCH-L1 expression. • KSHV LANA is sufficient for the induction of uch-l1. • Co-infection with KSHV and EBV (observed in some PELs) results in the additive induction of uch-l1. • EBV LMP1 also induced UCH-L1 expression. • LANA- and LMP1-mediated activation of the uch-l1 promoter is in part through RBP-Jκ.

  13. Nominal dysphasia and euphoria caused by EBV encephalitis

    PubMed Central

    Carman, Kursat Bora; Yakut, Ayten; Ekici, Arzu; Isikay, Sedat

    2013-01-01

    Encephalitis is an uncommon neurological complication of Ebstein-Barr virus (EBV) infection and usually presents with confusion, decreased level of consciousness, fever, epileptic seizure, emotional instability and chorea. We present a patient with EBV encephalitis, characterised by nominal dysphasia, euphoria and personality changes. PMID:23307455

  14. The Epstein-Barr virus (EBV)-encoded protein kinase, EBV-PK, but not the thymidine kinase (EBV-TK), is required for ganciclovir and acyclovir inhibition of lytic viral production.

    PubMed

    Meng, Qiao; Hagemeier, Stacy R; Fingeroth, Joyce D; Gershburg, Edward; Pagano, Joseph S; Kenney, Shannon C

    2010-05-01

    Ganciclovir (GCV) and acyclovir (ACV) are guanine nucleoside analogues that inhibit lytic herpesvirus replication. GCV and ACV must be monophosphorylated by virally encoded enzymes to be converted into nucleotides and incorporated into viral DNA. However, whether GCV and/or ACV phosphorylation in Epstein-Barr virus (EBV)-infected cells is mediated primarily by the EBV-encoded protein kinase (EBV-PK), the EBV-encoded thymidine kinase (EBV-TK), or both is controversial. To examine this question, we constructed EBV mutants containing stop codons in either the EBV-PK or EBV-TK open reading frame and selected for stable 293T clones latently infected with wild-type EBV or each of the mutant viruses. Cells were induced to the lytic form of viral replication with a BZLF1 expression vector in the presence and absence of various doses of GCV and ACV, and infectious viral titers were determined by a green Raji cell assay. As expected, virus production in wild-type EBV-infected 293T cells was inhibited by both GCV (50% inhibitory concentration [IC(50)] = 1.5 microM) and ACV (IC(50) = 4.1 microM). However, the EBV-PK mutant (which replicates as well as the wild-type (WT) virus in 293T cells) was resistant to both GCV (IC(50) = 19.6 microM) and ACV (IC(50) = 36.4 microM). Expression of the EBV-PK protein in trans restored GCV and ACV sensitivity in cells infected with the PK mutant virus. In contrast, in 293T cells infected with the TK mutant virus, viral replication remained sensitive to both GCV (IC(50) = 1.2 microM) and ACV (IC(50) = 2.8 microM), although susceptibility to the thymine nucleoside analogue, bromodeoxyuridine, was reduced. Thus, EBV-PK but not EBV-TK mediates ACV and GCV susceptibilities.

  15. An Animal Model for Human EBV-Associated Hemophagocytic Syndrome

    PubMed Central

    Hayashi, Kazuhiko; Ohara, Nobuya; Teramoto, Norihiro; Onoda, Sachiyo; Chen, Hong-Li; Oka, Takashi; Kondo, Eisaku; Yoshino, Tadashi; Takahashi, Kiyoshi; Yates, John; Akagi, Tadaatsu

    2001-01-01

    Epstein-Barr virus-associated hemophagocytic syndrome (EBV-AHS) is often associated with fatal infectious mononucleosis. However, the animal model for EBV-AHS has not been developed. We reported the first animal model for EBV-AHS using rabbits infected with EBV-related herpesvirus of baboon (HVP). Eleven of 13 (85%) rabbits inoculated intravenously with HVP-producing cells developed fatal lymphoproliferative disorders (LPD) between 22 and 105 days after inoculation. LPD was also accompanied by hemophagocytic syndrome (HPS) in nine of these 11 rabbits. The peroral spray of cell-free HVP induced the virus infection with increased anti-EBV-viral capsid antigen-IgG titers in three of five rabbits, and two of these three infected rabbits died of LPD with HPS. Autopsy revealed hepatosplenomegaly and swollen lymph nodes. Atypical lymphoid T cells expressing EBV-encoded small RNA-1 infiltrated diffusely in many organs, frequently involving the lymph nodes, spleen, and liver. Hemophagocytic histiocytosis was observed in the lymph nodes, spleen, bone marrow, and thymus. HVP-DNA was detected in the tissues and peripheral blood from the infected rabbits by polymerase chain reaction or Southern blot analysis. Reverse transcriptase-polymerase chain reaction revealed both HVP-EBNA1 and HVP-EBNA2 transcripts, suggesting latency type III infection. These data indicate that the high rate of rabbit LPD with HPS induction is caused by HVP. This system is useful for studying the pathogenesis, prevention, and treatment of human EBV-AHS. PMID:11290571

  16. Epstein-Barr virus (EBV)-related lymphoproliferative disorder with subsequent EBV-negative T-cell lymphoma.

    PubMed

    Tao, Q; Srivastava, G; Loke, S L; Liang, R H; Liu, Y T; Ho, F C

    1994-07-01

    A 58-year-old Chinese man presented initially with generalized lymphadenopathy, and lymph-node biopsy showed disturbed architecture with preponderance of large B-blasts mixed with numerous CD8+ T lymphocytes, consistent with an acute Epstein-Barr virus (EBV) infection. Immunohistological and gene rearrangement studies confirmed the absence of clonal T or B cells. Polyclonal EBV with lytic infection was detected by Southern blot hybridization (SoBH). Expression of EBV proteins (EBNA2, LMP and ZEBRA) was detected in a proportion of cells by immunostaining. EBV-lytic proteins EA-D, VCA, MA were also detected in rare scattered cells. Double immunostaining showed that the LMP-positive cells were of B and of T phenotype: 73% CD19+, 26% CD2+, 23% CD3+, 8% CD4+, 17% CD8+. After biopsy, there was spontaneous regression of lymph-node enlargement, but lymphadenopathy recurred 8 months later, and the second lymph-node biopsy showed T-cell lymphoma, confirmed by detection of clonally rearranged T-cell-receptor beta-chain gene. However, EBV genome could not be detected in the second biopsy by SoBH, in situ hybridization for EBV-encoded EBER RNA, and immunostaining for EBNA2, LMP and ZEBRA was also negative. This case is of special interest because an EBV-negative T-cell lymphoma developed shortly after an acute episode of EBV-related lymphoproliferation, even though many EBV-positive T cells were detected during the acute episode. EBV was apparently not a direct cause of the lymphoma, but the close temporal association of the 2 lesions supports the hypothesis that EBV can act as a co-factor in lymphomagenesis.

  17. Innate Immune Recognition of EBV.

    PubMed

    Lünemann, Anna; Rowe, Martin; Nadal, David

    2015-01-01

    The ability of Epstein-Barr virus (EBV) to establish latency despite specific immune responses and to successfully persist lifelong in the human host shows that EBV has developed powerful strategies and mechanisms to exploit, evade, abolish, or downsize otherwise effective immune responses to ensure its own survival. This chapter focuses on current knowledge on innate immune responses against EBV and its evasion strategies for own benefit and summarizes the questions that remain to be tackled. Innate immune reactions against EBV originate both from the main target cells of EBV and from nontarget cells, which are elements of the innate immune system. Thus, we structured our review accordingly but with a particular focus on the innate recognition of EBV in its two stages in its life cycle, latent state and lytic replication. Specifically, we discuss (I) innate sensing and resulting innate immune responses against EBV by its main target cells, focusing on (i) EBV transmission between epithelial cells and B cells and their life cycle stages; and (ii) elements of innate immunity in EBV's target cells. Further, we debate (II) the innate recognition and resulting innate immune responses against EBV by cells other than the main target cells, focusing on (iii) myeloid cells: dendritic cells, monocytes, macrophages, and neutrophil granulocytes; and (iv) natural killer cells. Finally, we address (III) how EBV counteracts or exploits innate immunity in its latent and lytic life cycle stages, concentrating on (v) TLRs; (vi) EBERs; and (vii) microRNAs. PMID:26428378

  18. EBV-miR-BHRF1-2 targets PRDM1/Blimp1: potential role in EBV lymphomagenesis

    PubMed Central

    Ma, J; Nie, K; Redmond, D; Liu, Y; Elemento, O; Knowles, D M; Tam, W

    2016-01-01

    PRDM1/Blimp1, a master regulator of B-cell terminal differentiation, has been identified as a tumor suppressor gene in aggressive lymphomas, including diffuse large B-cell lymphoma (DLBCL). It has been shown in DLBCL and Hodgkin lymphoma that PRDM1 is downregulated by cellular microRNAs. In this study, we identify the Epstein–Barr virus (EBV) microRNA (miRNA), EBV-miR-BHRF1-2, as a viral miRNA regulator of PRDM1. EBV-miR-BHRF1-2 repressed luciferase reporter activity by specific interaction with the seed region within the PRDM1 3' untranslated region. EBV-miR-BHRF1-2 inhibition upregulated PRDM1 protein expression in lymphoblastoid cell lines (LCL), supporting a role of miR-BHRF1-2 in PRDM1 downregulation in vivo. Discordance of PRDM1 messenger RNA and protein expressions is associated with high EBV-miR-BHRF1-2 levels in LCLs and primary post-transplant EBV-positive DLBCL. Enforced expression of PRDM1-induced apoptosis and cell cycle arrest in LCL cells. Inhibition of EBV-miR-BHRF1-2 negatively regulates cell cycle and decreases expression of SCARNA20, a small nucleolar RNA that is also downregulated by PRDM1 overexpression. The interaction between EBV-miR-BHRF1-2 and PRDM1 may be one of the mechanisms by which EBV-miR-BHRF1-2 promotes EBV lymphomagenesis. Our results support the potential of EBV-miR-BHRF1-2 as a therapeutic target in EBV-associated lymphoma. PMID:26530011

  19. Dissecting the contribution of EBNA3C domains important for EBV-induced B-cell growth and proliferation

    PubMed Central

    Lu, Jie; Prasad Aj, Mahadesh; Banerjee, Shuvomoy; Robertson, Erle S.

    2015-01-01

    Epstein-Barr virus (EBV) is an oncogenic gammaherpes virus which is linked to pathogenesis of several human lymphatic malignancies. The EBV essential latent antigen EBNA3C is critical for efficient conversion of primary human B-lymphocytes to lymphoblastic cell lines and for continued LCL growth. EBNA3C, an EBV latent antigen with oncogenic potential can bind and regulate the functions of a wide range of cellular transcription factors. In our current reverse genetics study, we deleted the full length EBNA3C, and independently the RBP-Jκ and Nm23-H1 binding sites within EBNA3C using BACmid recombinant engineering methodology. Our experiments demonstrated that deletion of the EBV EBNA3C open reading frame (ORF) and more specifically the residues 621–675 which binds Nm23H1 and SUMO-1 showed a significant reduction in the ability of the cells to proliferate. Furthermore, they exhibited lower infectivity of human peripheral blood mononuclear cells (PBMCs). We also showed that recombinant EBV with deletions of the EBNA3C ORF, as well as a recombinant with residues 621–675 within EBNA3C ORF deleted had diminished abilities to activate CD40. Our study also revealed that the full length (1–992) and 621–675 aa deletions of EBNA3C when compared to wild type EBV infected PBMCs had differential expression patterns for the phosphorylation of MAP kinases specifically p38, JNK and ERK. Regulation of β-catenin also differed among wild type and EBNA3C deleted mutants. These temporal differences in signaling activities of these recombinant viruses in PBMCs is likely important in defining their functional importance in EBV-mediated B-cell transformation. PMID:26336822

  20. A familial syndrome of susceptibility to chronic active Epstein-Barr virus infection.

    PubMed Central

    Joncas, J. H.; Ghibu, F.; Blagdon, M.; Montplaisir, S.; Stefanescu, I.; Menezes, J.

    1984-01-01

    In two members of a family (daughter and father) active Epstein-Barr virus (EBV) infections persisted over periods of 4 and 3 years respectively (possibly 10 years in the father). Both had persistent splenomegaly and occasional bouts of unexplained fever but lived otherwise normal lives. The other members of the family (mother and son) were healthy. The titres of antibody to the EBV viral capsid antigen (VCA) and early antigen (EA) were extremely high in the daughter's blood, whereas the titres of antibody to the Epstein-Barr nuclear antigen were low in the daughter's blood and undetectable in the father's. Target cells of the EBV infection that were obtained from the daughter's blood were established in culture with great difficulty and showed increased expression of VCA and EA. Other immunologic investigations in the two patients revealed that the ratio of helper to suppressor T lymphocytes was inverted, natural killer-cell activity was abnormally low, lymphocyte responses to certain mitogens were depressed and there was a serum factor blocking mitogen-induced transformation. The possibility that the patients' unusual susceptibility to EBV infection represented an inherited syndrome (perhaps X-linked) is discussed. PMID:6318944

  1. Transduction of Primary Lymphocytes with Epstein-Barr Virus (EBV) Latent Membrane Protein-Specific T-Cell Receptor Induces Lysis of Virus-Infected Cells: A Novel Strategy for the Treatment of Hodgkin’s Disease and Nasopharyngeal Carcinoma

    PubMed Central

    Jurgens, Lisa A.; Khanna, Rajiv; Weber, James; Orentas, Rimas J.

    2010-01-01

    Adoptive immunotherapy with in vitro expanded cytotoxic T lymphocytes specific for Epstein-Barr virus (EBV) can successfully treat post-transplant lymphoproliferative disease (PTLD). However, extension of a similar strategy to Hodgkin’s disease (HD) and nasopharyngeal carcinoma (NPC) is limited by the poor immunogenicity of the limited set of EBV latency antigens expressed in these malignancies, making T-cell expansion difficult. Retroviral transduction of LMP-specific T-cell receptors (TCR) into activated T lymphocytes may provide a universal, MHC-restricted, means to generate effector cells without the need for tissue culture based methods of CTL expansion. We report the transfer of two LMP2-specific TCRs from human T-cell clones (HLA-A2 and HLA-A23,24 restricted) that confer the ability to lyse EBV-immortalized B-lymphoblastoid cell lines (B-LCL). B-LCL are the best model for native expression of LMP2. We also demonstrate the rapid transfer of the TCR by nucleofection of primary T cells using a simple plasmid-based vector. The ability to detect nucleofected TCRVβ chain by antibody, fully assembled TCR by tetramer, and peptide-MHC-specific lytic activity indicates that nucleofection can serve as a tool for rapid screening of TCR specificity. PMID:16418800

  2. Indole-3-carbinol induces cMYC and IAP-family downmodulation and promotes apoptosis of Epstein-Barr virus (EBV)-positive but not of EBV-negative Burkitt's lymphoma cell lines.

    PubMed

    Perez-Chacon, Gema; de Los Rios, Cristobal; Zapata, Juan M

    2014-11-01

    Indole-3-carbinol (I3C) is a natural product found in broadly consumed plants of the Brassica genus, such as broccoli, cabbage, and cauliflower, which exhibits anti-tumor effects through poorly defined mechanisms. I3C can be orally administered and clinical trials have demonstrated that I3C and derivatives are safe in humans. In this study we show that I3C efficiently induces apoptosis in cell lines derived from EBV-positive Burkitt's lymphomas (virus latency I/II), while it does not have any cytotoxic activity against EBV-negative Burkitt's lymphomas and immortalized EBV-infected lymphoblastoid cell lines (virus latency III). The effect of I3C in EBV-positive Burkitt's lymphoma is very specific, since only I3C and its C6-methylated derivative, but not other 3-substituted indoles, have an effect on cell viability. I3C treatment caused apoptosis characterized by loss of mitochondria membrane potential and caspase activation. I3C alters the expression of proteins involved in the control of apoptosis and transcription regulation in EBV-positive Burkitt's lymphoma cell lines. Among those, cMYC, cIAP1/2 and XIAP downmodulation at mRNA and protein level precede apoptosis induction, thus suggesting a role in I3C cytotoxicity. We also showed that I3C and, more particularly, its condensation dimer 3,3'-diindolylmethane (DIM) prolonged survival and reduced tumor burden of mice xenotransplanted with EBV-positive Burkitt's lymphoma Daudi cells. In summary these results, together with previous reports from clinical trials indicating the lack of toxicity in humans of I3C and derivatives, support the use of these compounds as a new therapeutic approach for treating patients with endemic (EBV-positive) Burkitt's lymphoma. PMID:25180456

  3. Assembly and Architecture of the EBV B Cell Entry Triggering Complex

    PubMed Central

    Sathiyamoorthy, Karthik; Jiang, Jiansen; Hu, Yao Xiong; Rowe, Cynthia L.; Möhl, Britta S.; Chen, Jia; Jiang, Wei; Mellins, Elizabeth D.; Longnecker, Richard; Zhou, Z. Hong; Jardetzky, Theodore S.

    2014-01-01

    Epstein-Barr Virus (EBV) is an enveloped double-stranded DNA virus of the gammaherpesvirinae sub-family that predominantly infects humans through epithelial cells and B cells. Three EBV glycoproteins, gH, gL and gp42, form a complex that targets EBV infection of B cells. Human leukocyte antigen (HLA) class II molecules expressed on B cells serve as the receptor for gp42, triggering membrane fusion and virus entry. The mechanistic role of gHgL in herpesvirus entry has been largely unresolved, but it is thought to regulate the activation of the virally-encoded gB protein, which acts as the primary fusogen. Here we study the assembly and function of the reconstituted B cell entry complex comprised of gHgL, gp42 and HLA class II. The structure from negative-stain electron microscopy provides a detailed snapshot of an intermediate state in EBV entry and highlights the potential for the triggering complex to bring the two membrane bilayers into proximity. Furthermore, gHgL interacts with a previously identified, functionally important hydrophobic pocket on gp42, defining the overall architecture of the complex and playing a critical role in membrane fusion activation. We propose a macroscopic model of the initiating events in EBV B cell fusion centered on the formation of the triggering complex in the context of both viral and host membranes. This model suggests how the triggering complex may bridge the two membrane bilayers, orienting critical regions of the N- and C- terminal ends of gHgL to promote the activation of gB and efficient membrane fusion. PMID:25144748

  4. Signal transducer and activator of transcription 3 limits Epstein-Barr virus lytic activation in B lymphocytes.

    PubMed

    Hill, Erik R; Koganti, Siva; Zhi, Jizu; Megyola, Cynthia; Freeman, Alexandra F; Palendira, Umaimainthan; Tangye, Stuart G; Farrell, Paul J; Bhaduri-McIntosh, Sumita

    2013-11-01

    Lytic activation of Epstein-Barr virus (EBV) is central to its life cycle and to most EBV-related diseases. However, not every EBV-infected B cell is susceptible to lytic activation. This lack of uniform susceptibility to lytic activation also directly impacts the success of viral oncolytic therapy for EBV cancers, yet determinants of susceptibility to lytic induction signals are not well understood. To determine if host factors influence susceptibility to EBV lytic activation, we developed a technique to separate lytic from refractory cells and reported that EBV lytic activation occurs preferentially in cells with lower levels of signal transducer and activator of transcription 3 (STAT3). Using this tool to detect single cells, we now extend the correlation between STAT3 and lytic versus refractory states to EBV-infected circulating B cells in patients with primary EBV infection, leading us to investigate whether STAT3 controls susceptibility to EBV lytic activation. In loss-of-function and gain-of-function studies in EBV-positive B lymphoma and lymphoblastoid cells, we found that the levels of functional STAT3 regulate susceptibility to EBV lytic activation. This prompted us to identify a pool of candidate cellular genes that might be regulated by STAT3 to limit EBV lytic activation. From this pool, we confirmed increases in transcript levels in refractory cells of a set of genes known to participate in transcription repression. Taken together, our findings place STAT3 at a critical crossroads between EBV latency and lytic activation, processes fundamental to EBV lymphomagenesis. PMID:23966384

  5. Signal transducer and activator of transcription 3 limits Epstein-Barr virus lytic activation in B lymphocytes.

    PubMed

    Hill, Erik R; Koganti, Siva; Zhi, Jizu; Megyola, Cynthia; Freeman, Alexandra F; Palendira, Umaimainthan; Tangye, Stuart G; Farrell, Paul J; Bhaduri-McIntosh, Sumita

    2013-11-01

    Lytic activation of Epstein-Barr virus (EBV) is central to its life cycle and to most EBV-related diseases. However, not every EBV-infected B cell is susceptible to lytic activation. This lack of uniform susceptibility to lytic activation also directly impacts the success of viral oncolytic therapy for EBV cancers, yet determinants of susceptibility to lytic induction signals are not well understood. To determine if host factors influence susceptibility to EBV lytic activation, we developed a technique to separate lytic from refractory cells and reported that EBV lytic activation occurs preferentially in cells with lower levels of signal transducer and activator of transcription 3 (STAT3). Using this tool to detect single cells, we now extend the correlation between STAT3 and lytic versus refractory states to EBV-infected circulating B cells in patients with primary EBV infection, leading us to investigate whether STAT3 controls susceptibility to EBV lytic activation. In loss-of-function and gain-of-function studies in EBV-positive B lymphoma and lymphoblastoid cells, we found that the levels of functional STAT3 regulate susceptibility to EBV lytic activation. This prompted us to identify a pool of candidate cellular genes that might be regulated by STAT3 to limit EBV lytic activation. From this pool, we confirmed increases in transcript levels in refractory cells of a set of genes known to participate in transcription repression. Taken together, our findings place STAT3 at a critical crossroads between EBV latency and lytic activation, processes fundamental to EBV lymphomagenesis.

  6. Epstein-Barr Virus (EBV) DNA in plasma is not encapsidated in patients with EBV-related malignancies.

    PubMed

    Ryan, Julie L; Fan, Hongxin; Swinnen, Lode J; Schichman, Steven A; Raab-Traub, Nancy; Covington, Mary; Elmore, Sandra; Gulley, Margaret L

    2004-06-01

    Epstein-Barr Virus (EBV), a ubiquitous gamma herpes virus, infects more than 95% of the human population before adulthood. Life-long persistence, usually without adverse health consequences, relies on a balance between viral latency, viral replication, and host immune response. Patients with EBV-related disease often have high levels of EBV DNA in their plasma. This study addresses whether this circulating, cell-free EBV DNA is encapsidated in virions or exists as naked genomes. First, an assay was developed, combining DNase I and quantitative real-time PCR, to discriminate encapsidated from naked EBV DNA. EBV DNA was almost always naked in the plasma of AIDS-related lymphoma patients (n = 11) and immunosuppressed/posttransplantation patients (n = 8). In contrast, infectious mononucleosis patients (n = 30) often had a mixture of encapsidated and naked EBV DNA. These findings may be important in understanding how viral load relates to disease status and in predicting response to nucleoside analogs and other antiviral therapies. PMID:15167006

  7. EBV glycoproteins: where are we now?

    PubMed Central

    Hutt-Fletcher, Lindsey M

    2015-01-01

    Glycoproteins are critical to virus entry, to spread within and between hosts and can modify the behavior of cells. Many viruses carry only a few, most found in the virion envelope. EBV makes more than 12, providing flexibility in how it colonizes its human host. Some are dedicated to getting the virus through the cell membrane and on toward the nucleus of the cell, some help guide the virus back out and on to the next cell in the same or a new host. Yet others undermine host defenses helping the virus persist for a lifetime, maintaining a presence that is mostly tolerated and serves to perpetuate EBV as one of the most common infections of man. PMID:26843889

  8. Increased expression of Toll-like receptors 7 and 9 in myasthenia gravis thymus characterized by active Epstein-Barr virus infection.

    PubMed

    Cavalcante, Paola; Galbardi, Barbara; Franzi, Sara; Marcuzzo, Stefania; Barzago, Claudia; Bonanno, Silvia; Camera, Giorgia; Maggi, Lorenzo; Kapetis, Dimos; Andreetta, Francesca; Biasiucci, Amelia; Motta, Teresio; Giardina, Carmelo; Antozzi, Carlo; Baggi, Fulvio; Mantegazza, Renato; Bernasconi, Pia

    2016-04-01

    Considerable data implicate the thymus as the main site of autosensitization to the acetylcholine receptor in myasthenia gravis (MG), a B-cell-mediated autoimmune disease affecting the neuromuscular junction. We recently demonstrated an active Epstein-Barr virus (EBV) infection in the thymus of MG patients, suggesting that EBV might contribute to the onset or maintenance of the autoimmune response within MG thymus, because of its ability to activate and immortalize autoreactive B cells. EBV has been reported to elicit and modulate Toll-like receptor (TLR) 7- and TLR9-mediated innate immune responses, which are known to favor B-cell dysfunction and autoimmunity. Aim of this study was to investigate whether EBV infection is associated with altered expression of TLR7 and TLR9 in MG thymus. By real-time PCR, we found that TLR7 and TLR9 mRNA levels were significantly higher in EBV-positive MG compared to EBV-negative normal thymuses. By confocal microscopy, high expression levels of TLR7 and TLR9 proteins were observed in B cells and plasma cells of MG thymic germinal centers (GCs) and lymphoid infiltrates, where the two receptors co-localized with EBV antigens. An increased frequency of Ki67-positive proliferating B cells was found in MG thymuses, where we also detected proliferating cells expressing TLR7, TLR9 and EBV antigens, thus supporting the idea that EBV-associated TLR7/9 signaling may promote abnormal B-cell activation and proliferation. Along with B cells and plasma cells, thymic epithelium, plasmacytoid dendritic cells and macrophages exhibited enhanced TLR7 and TLR9 expression in MG thymus; TLR7 was also increased in thymic myeloid dendritic cells and its transcriptional levels positively correlated with those of interferon (IFN)-β. We suggested that TLR7/9 signaling may be involved in antiviral type I IFN production and long-term inflammation in EBV-infected MG thymuses. Our overall findings indicate that EBV-driven TLR7- and TLR9-mediated innate immune

  9. In-cell infection: a novel pathway for Epstein-Barr virus infection mediated by cell-in-cell structures

    PubMed Central

    Ni, Chao; Chen, Yuhui; Zeng, Musheng; Pei, Rongjuan; Du, Yong; Tang, Linquan; Wang, Mengyi; Hu, Yazhuo; Zhu, Hanyu; He, Meifang; Wei, Xiawei; Wang, Shan; Ning, Xiangkai; Wang, Manna; Wang, Jufang; Ma, Li; Chen, Xinwen; Sun, Qiang; Tang, Hong; Wang, Ying; Wang, Xiaoning

    2015-01-01

    Epstein-Barr virus (EBV) can infect both susceptible B lymphocytes and non-susceptible epithelial cells (ECs). Viral tropism analyses have revealed two intriguing means of EBV infection, either by a receptor-mediated infection of B cells or by a cell-to-cell contact-mediated infection of non-susceptible ECs. Herein, we report a novel “in-cell infection” mechanism for EBV infection of non-susceptible ECs through the formation of cell-in-cell structures. Epithelial CNE-2 cells were invaded by EBV-infected Akata B cells to form cell-in-cell structures in vitro. Such unique cellular structures could be readily observed in the specimens of nasopharyngeal carcinoma. Importantly, the formation of cell-in-cell structures led to the autonomous activation of EBV within Akata cells and subsequent viral transmission to CNE-2 cells, as evidenced by the expression of viral genes and the presence of virion particles in CNE-2 cells. Significantly, EBV generated from in-cell infected ECs displayed altered tropism with higher infection efficacy to both B cells and ECs. In addition to CNE-2 tumor cells, cell-in-cell structure formation could also mediate EBV infection of NPEC1-Bmi1 cells, an immortalized nasopharyngeal epithelial cell line. Furthermore, efficient infection by this mechanism involved the activation of the PI3K/AKT signaling pathway. Thus, our study identified “in-cell infection” as a novel mechanism for EBV infection. Given the diversity of virus-infected cells and the prevalence of cell-in-cell structures during chronic infection, we speculate that “in-cell infection” is likely a general mechanism for EBV and other viruses to infect non-susceptible ECs. PMID:25916549

  10. EBV-driven B-cell lymphoproliferative disorders: from biology, classification and differential diagnosis to clinical management

    PubMed Central

    Ok, Chi Young; Li, Ling; Young, Ken H

    2015-01-01

    Epstein–Barr virus (EBV) is a ubiquitous herpesvirus, affecting >90% of the adult population. EBV targets B-lymphocytes and achieves latent infection in a circular episomal form. Different latency patterns are recognized based on latent gene expression pattern. Latent membrane protein-1 (LMP-1) mimics CD40 and, when self-aggregated, provides a proliferation signal via activating the nuclear factor-kappa B, Janus kinase/signal transducer and activator of transcription, phosphoinositide 3-kinase/Akt (PI3K/Akt) and mitogen-activated protein kinase pathways to promote cellular proliferation. LMP-1 also induces BCL-2 to escape from apoptosis and gives a signal for cell cycle progression by enhancing cyclin-dependent kinase 2 and phosphorylation of retinoblastoma (Rb) protein and by inhibiting p16 and p27. LMP-2A blocks the surface immunoglobulin-mediated lytic cycle reactivation. It also activates the Ras/PI3K/Akt pathway and induces Bcl-xL expression to promote B-cell survival. Recent studies have shown that ebv-microRNAs can provide extra signals for cellular proliferation, cell cycle progression and anti-apoptosis. EBV is well known for association with various types of B-lymphocyte, T-lymphocyte, epithelial cell and mesenchymal cell neoplasms. B-cell lymphoproliferative disorders encompass a broad spectrum of diseases, from benign to malignant. Here we review our current understanding of EBV-induced lymphomagenesis and focus on biology, diagnosis and management of EBV-associated B-cell lymphoproliferative disorders. PMID:25613729

  11. Detection of Active Epstein-Barr Virus Infection in Duodenal Mucosa of Patients With Refractory Celiac Disease.

    PubMed

    Perfetti, Vittorio; Baldanti, Fausto; Lenti, Marco Vincenzo; Vanoli, Alessandro; Biagi, Federico; Gatti, Marta; Riboni, Roberta; Dallera, Elena; Paulli, Marco; Pedrazzoli, Paolo; Corazza, Gino Roberto

    2016-08-01

    Refractory celiac disease is characterized by mucosal damage in patients with celiac disease despite a gluten-free diet. Little is known about the mechanisms that cause persistent intestinal inflammation in these patients. We performed a case-control study of 17 consecutive patients diagnosed with refractory celiac disease from 2001 through 2014 (median age, 51 y; 10 women) and 24 patients with uncomplicated celiac disease (controls) to determine whether refractory disease is associated with infection by lymphotropic oncogenic viruses. We performed real-time PCR analyses of duodenal biopsy samples from all patients to detect Epstein-Barr virus (EBV), human herpesvirus-8, and human T-cell lymphotropic virus-I, -II, or -III. We used in situ hybridization and immunohistochemical analyses to identify infected cells and viral proteins. We did not detect human herpesvirus-8 or human T-cell lymphotropic viruses in any of the biopsy specimens. However, 12 of 17 (70.5%) biopsy specimens from patients with refractory celiac disease were positive for EBV, compared with 4 of 24 (16.6%) biopsy specimens from controls (P < .001). EBV was detected in inflammatory cells and enterocytes. An analysis of latency- and replication-associated proteins confirmed active infection. Further studies are needed to determine whether EBV infection contributes to the pathogenesis of refractory celiac disease and enteropathy-associated T-cell lymphoma.

  12. Nonsteroidal Anti-Inflammatory Drugs Quickly Resolve Symptoms Associated with EBV-Induced Infectious Mononucleosis in Patients with Atopic Predispositions

    PubMed Central

    Kazama, Itsuro; Miura, Chieko; Nakajima, Toshiyuki

    2016-01-01

    Case series Patient: Female, 24 • Male, 35 Final Diagnosis: EBV-induced infectious mononucleosis Symptoms: Fever • general malaise • lymphadenopathy Medication: — Clinical Procedure: Physical examination and serological testing Specialty: Infectious diseases Objective: Rare co-existance of disease or pathology Background: Infectious mononucleosis is a clinical syndrome most commonly associated with primary Epstein-Barr virus (EBV) infection. In adults, the symptoms can often be severe and prolonged, sometimes causing serious complications. Analgesic or antipyretic drugs are normally used to relieve the symptoms. However, there is no causal treatment for the disease. Case Report: Two cases of adult patients with atopic predispositions developed nocturnal fever, general fatigue, pharyngitis and lymphadenopathy after an exacerbation of atopic symptoms or those of allergic rhinitis. Due to the positive results for EBV viral-capsid antigen (VCA) IgM and negative results for EBV nuclear antigen (EBNA) IgG, diagnoses of infectious mononucleosis induced by EBV were made in both cases. Although oral antibiotics or acetaminophen alone did not improve the deteriorating symptoms, including fever, headache and general fatigue, nonsteroidal anti-inflammatory drugs (NSAIDs), such as tiaramide or loxoprofen, completely improved the symptoms quickly after the initiation. Conclusions: In these cases, given the atopic predispositions of the patients, an enhanced immunological response was likely to be mainly responsible for the pathogenesis of the symptoms. In such cases, NSAIDs, that are known to reduce the activity of EBV, may dramatically improve the deteriorating symptoms quickly after the initiation. In the present cases, the immunosuppressive property of these drugs was considered to suppress the activity of lymphocytes and thus provide the rapid and persistent remission of the disease. PMID:26874639

  13. Prognostic Utility of Anti-EBV Antibody Testing for Defining NPC Risk among Individuals from High-Risk NPC Families

    PubMed Central

    Yu, Kelly J.; Hsu, Wan-Lun; Pfeiffer, Ruth M.; Chiang, Chun-Ju; Wang, Cheng-Ping; Lou, Pei-Jen; Cheng, Yu-Juen; Gravitt, Patti; Diehl, Scott R.; Goldstein, Alisa M.; Chen, Chien-Jen; Hildesheim, Allan

    2012-01-01

    Purpose Epstein–Barr virus (EBV) infection and a family history of nasopharyngeal carcinoma (NPC) are associated with NPC risk. We examined the risk associated with EBV markers and their clinical utility to identify NPC susceptibles within high-risk NPC families. Experimental Design We evaluated antibody titers against viral capsid antigen (VCA) IgA, EBV nuclear antigen-1 (EBNA1) IgA, and DNase among unaffected relatives of NPC cases from 358 multiplex families in Taiwan. Incident NPC cases were identified via linkage to the National Cancer Registry. Clinical examinations of 924 individuals were also done to identify occult, asymptomatic NPC. Baseline EBV serology was used to estimate NPC risk using rate ratios with 95% CI. Associated sensitivity/specificity and receiver operating characteristic (ROC) curves were calculated. Results A total of 2,444 unaffected individuals with 15,519 person-years (6.5 years median follow-up) yielded 14 incident NPC cases (nearly 11 times the general population rate). The absolute rate of NPC among anti-EBV EBNA1 IgA seropositives using a standard positivity cutoff versus an optimized cutoff point defined by ROC analyses was 265/100,000 person-years with a 4.7-fold increased risk of NPC (95% CI: 1.4–16) and 166/100,000 person-years with a 6.6-fold increase (95% CI: 1.5–61), respectively. Sensitivity and specificity using the optimized positivity cutoff points were 85.7% and 51.2%, respectively. It is estimated that active evaluation of 49% of individuals from high-risk NPC families seropositive for this marker could lead to earlier detection of up to 86% of NPC cases. Risks associated with the other three EBV markers were weaker. Conclusions Future efforts are needed to identify susceptibility markers among high-risk NPC families that maximize both sensitivity and specificity. PMID:21447725

  14. Activation of lytic cycle of Epstein-Barr virus by suberoylanilide hydroxamic acid leads to apoptosis and tumor growth suppression of nasopharyngeal carcinoma.

    PubMed

    Hui, K F; Ho, Dona N; Tsang, C M; Middeldorp, Jaap M; Tsao, George S W; Chiang, Alan K S

    2012-10-15

    Nasopharyngeal carcinoma (NPC) is strongly associated with Epstein-Barr virus (EBV). We reported that suberoylanilide hydroxamic acid (SAHA) induced EBV lytic cycle in EBV-positive gastric carcinoma cells and mediated enhanced cell death. However, expression of EBV lytic proteins was thought to exert antiapoptotic effect in EBV-infected cells. Here, we examined the in vitro and in vivo effects of SAHA on EBV lytic cycle induction in NPC cells and investigated the cellular consequences. Micromolar concentrations of SAHA significantly induced EBV lytic cycle in EBV-positive NPC cells. Increased apoptosis and proteolytic cleavage of poly(ADP-ribose) polymerase and caspase-3, -7 and -9 in EBV-positive versus EBV-negative NPC cells were observed. More than 85% of NPC cells expressing immediate-early (Zta), early (BMRF1) or late (gp350/220) lytic proteins coexpressed cleaved caspase-3. Tracking of expression of EBV lytic proteins and cleaved caspase-3 over time demonstrated that NPC cells proceeded to apoptosis following EBV lytic cycle induction. Inhibition of EBV DNA replication and late lytic protein expression by phosphonoformic acid did not impact on SAHA's induced cell death in NPC, indicating that early rather than late phase of EBV lytic cycle contributed to the apoptotic effect. In vivo effects of SAHA on EBV lytic cycle induction and tumor growth suppression were also observed in NPC xenografts in nude mice. Taken together, our data indicated that activation of lytic cycle from latent cycle of EBV by SAHA leads to apoptosis and tumor growth suppression of NPC thereby providing experimental evidence for virus-targeted therapy against EBV-positive cancer.

  15. Differential cytokine expression in EBV positive peripheral T cell lymphomas.

    PubMed Central

    Ho, J W; Liang, R H; Srivastava, G

    1999-01-01

    AIM: To investigate whether specific cytokines are secreted locally at the tumour site in Epstein-Barr virus (EBV) positive peripheral T cell lymphoma (PTCL). METHODS: An RNase protection assay system was used to study the differential expression of 21 cytokines in parallel in eight cases of EBV positive non-nasal PTCL, and compared with 11 EBV negative non-nasal PTCLs and three EBV positive nasal natural killer (NK) cell lymphomas. RESULTS: Among the eight EBV positive cases, interferon gamma (IFN-gamma), lymphotoxin beta (LT beta), interleukin 10 (IL-10), tumour necrosis factor alpha (TNF-alpha), transforming growth factor beta 1 (TGF-beta 1), and IL-1 receptor a (IL-Ra) were frequently detectable. IL-15, IL-6, IL-4, IL-1 beta, TNF-beta, and IL-9 were sporadically detectable. Of the frequently detectable cytokines, IFN-gamma and LT beta were commonly detected in the EBV negative cases. For cases with > 50% EBV encoded small non-polyadenylated RNA (EBER) positive cells, IL-10, TNF-alpha, and TGF-beta 1 were detected in three of three cases, and IL-1Ra in two of three cases. For cases with < 20% EBER positive cells, IL-10 was detected in three of five cases, TNF-alpha in two of four cases, but TGF-beta 1 and IL-1Ra were not detected. Interestingly, IL-6 was detected in two of three cases with > 50% EBER positive cells, but only in one of five cases with < 20% EBER positive cells. For comparison, in NK cell lymphomas, IL-10, TNF-alpha, IL-1Ra, and IL-6 were all detectable, but TGF-beta 1 was not detected at all. Immunohistochemical staining revealed IL-10 in many cells; in contrast, EBV latent membrane protein 1 (LMP1) was only found to be positive in isolated cells. CONCLUSIONS: Certain cytokines, such as IL-10 and TNF-alpha, might be expressed preferentially in EBV positive peripheral T cell lymphomas. It is likely that such a cytokine environment enhances EBV infection and contributes towards tumorigenesis. PMID:10748876

  16. Differentiation-Dependent KLF4 Expression Promotes Lytic Epstein-Barr Virus Infection in Epithelial Cells

    PubMed Central

    Nawandar, Dhananjay M.; Wang, Anqi; Makielski, Kathleen; Lee, Denis; Ma, Shidong; Barlow, Elizabeth; Reusch, Jessica; Jiang, Ru; Wille, Coral K.; Greenspan, Deborah; Greenspan, John S.; Mertz, Janet E.; Hutt-Fletcher, Lindsey; Johannsen, Eric C.; Lambert, Paul F.; Kenney, Shannon C.

    2015-01-01

    Epstein-Barr virus (EBV) is a human herpesvirus associated with B-cell and epithelial cell malignancies. EBV lytically infects normal differentiated oral epithelial cells, where it causes a tongue lesion known as oral hairy leukoplakia (OHL) in immunosuppressed patients. However, the cellular mechanism(s) that enable EBV to establish exclusively lytic infection in normal differentiated oral epithelial cells are not currently understood. Here we show that a cellular transcription factor known to promote epithelial cell differentiation, KLF4, induces differentiation-dependent lytic EBV infection by binding to and activating the two EBV immediate-early gene (BZLF1 and BRLF1) promoters. We demonstrate that latently EBV-infected, telomerase-immortalized normal oral keratinocyte (NOKs) cells undergo lytic viral reactivation confined to the more differentiated cell layers in organotypic raft culture. Furthermore, we show that endogenous KLF4 expression is required for efficient lytic viral reactivation in response to phorbol ester and sodium butyrate treatment in several different EBV-infected epithelial cell lines, and that the combination of KLF4 and another differentiation-dependent cellular transcription factor, BLIMP1, is highly synergistic for inducing lytic EBV infection. We confirm that both KLF4 and BLIMP1 are expressed in differentiated, but not undifferentiated, epithelial cells in normal tongue tissue, and show that KLF4 and BLIMP1 are both expressed in a patient-derived OHL lesion. In contrast, KLF4 protein is not detectably expressed in B cells, where EBV normally enters latent infection, although KLF4 over-expression is sufficient to induce lytic EBV reactivation in Burkitt lymphoma cells. Thus, KLF4, together with BLIMP1, plays a critical role in mediating lytic EBV reactivation in epithelial cells. PMID:26431332

  17. Gold nano-particles (AuNPs) carrying anti-EBV-miR-BART7-3p inhibit growth of EBV-positive nasopharyngeal carcinoma

    PubMed Central

    Wang, Jianguo; Lyu, Xiaoming; Chen, Yuxiang; Liu, Jinkun; Cai, Hongbing; Wang, Ying; Li, Xin

    2015-01-01

    Epstein-Barr virus (EBV) infection is a major etiological factor for nasopharyngeal carcinoma (NPC). Several EBV-encoded BART miRNAs have been associated with viral latency, immune escape, cell survival, cell proliferation and apoptosis. Here, we report that EBV-miR-BART7-3p, an EBV-encoded BART miRNA highly expressed in NPC, was correlated with cell-cycle progression in vitro and increased tumor formation in vivo. This viral miRNA stimulated the PTEN/PI3K/Akt pathway and induced c-Myc and c-Jun. Knockdown of PTEN mimicked EBV-miR-BART7-3p-induced tumorigenic phenotype. Based on these results, we conducted a therapeutic experiment by using gold nano-particles (AuNPs) carrying anti-EBV-miR-BART7-3p. Silencing of EBV-miR-BART7-3p reduced tumor growth in animal model. We conclude that EBV-miR-BART7-3p favors carcinogenesis, representing a potential target for miRNA-based therapy. PMID:25691053

  18. About Epstein-Barr Virus (EBV)

    MedlinePlus

    ... Providers Laboratory Testing References & Resources About Epstein-Barr Virus (EBV) Recommend on Facebook Tweet Share Compartir On ... Page Symptoms Transmission Diagnosis Prevention & Treatment Epstein-Barr virus (EBV), also known as human herpesvirus 4, is ...

  19. Epstein-Barr virus-driven lymphomagenesis in the context of human immunodeficiency virus type 1 infection.

    PubMed

    Petrara, Maria R; Freguja, Riccardo; Gianesin, Ketty; Zanchetta, Marisa; De Rossi, Anita

    2013-01-01

    Epstein-Barr virus (EBV) is a ubiquitous human γ-herpes virus which establishes a life-long asymptomatic infection in immunocompetent hosts. In human immunodeficiency virus type 1 (HIV-1) infected patients, the impaired immunosurveillance against EBV may favor the development of EBV-related diseases, ranging from lymphoproliferative disorders to B cell non-Hodgkin's lymphomas (NHL). Antiretroviral therapy (ART) has significantly modified the natural course of HIV-1 infection, resulting in decreased HIV-1 plasmaviremia, increased CD4 lymphocytes, and decreased opportunistic infections, indicating a restoration of immune functions. However, the impact of ART appears to be less favorable on EBV-related malignancies than on other AIDS-defining tumors, such as Kaposi's sarcoma, and NHL remains the most common cancer during the ART era. EBV-driven tumors are associated with selective expression of latent oncogenic proteins, but uncontrolled lytic cycle with virus replication and/or reactivation may favor cell transformation, at least in the early phases. Several host's factors may promote EBV reactivation and replication; besides immunodepression, inflammation/chronic immune stimulation may play an important role. Microbial pathogen-associated molecular patterns and endogenous damage-associated molecular patterns, through Toll-like receptors, activate the immune system and may promote EBV reactivation and/or polyclonal expansion of EBV-infected cells. A body of evidence suggests that chronic immune stimulation is a hallmark of HIV-1 pathogenesis and may persist even in ART-treated patients. This review focuses on lymphomagenesis driven by EBV both in the context of the natural history of HIV-1 infection and in ART-treated patients. Understanding the mechanisms involved in the expansion of EBV-infected cells is a premise for the identification of prognostic markers of EBV-associated malignancies. PMID:24151490

  20. EBV reactivation as a target of luteolin to repress NPC tumorigenesis

    PubMed Central

    Wu, Chung-Chun; Fang, Chih-Yeu; Hsu, Hui-Yu; Chuang, Hsin-Ying; Cheng, Yu-Jhen; Chen, Yen-Ju; Chou, Sheng-Ping; Huang, Sheng-Yen; Lin, Su-Fang; Chang, Yao; Tsai, Ching-Hwa; Chen, Jen-Yang

    2016-01-01

    Nasopharyngeal carcinoma (NPC) is a malignancy derived from the epithelial cells of the nasopharynx. Although a combination of radiotherapy with chemotherapy is effective for therapy, relapse and metastasis after remission remain major causes of mortality. Epstein-Barr virus (EBV) is believed to be one of causes of NPC development. We demonstrated previously that EBV reactivation is important for the carcinogenesis of NPC. We sought, therefore, to determine whether EBV reactivation can be a target for retardation of relapse of NPC. After screening, we found luteolin is able to inhibit EBV reactivation. It inhibited EBV lytic protein expression and repressed the promoter activities of two major immediate-early genes, Zta and Rta. Furthermore, luteolin was shown to reduce genomic instability induced by recurrent EBV reactivation in NPC cells. EBV reactivation-induced NPC cell proliferation and migration, as well as matrigel invasiveness, were also repressed by luteolin treatment. Tumorigenicity in mice, induced by EBV reactivation, was decreased profoundly following luteolin administration. Together, these results suggest that inhibition of EBV reactivation is a novel approach to prevent the relapse of NPC. PMID:26967558

  1. Atypical prediagnosis Epstein-Barr virus serology restricted to EBV-positive Hodgkin lymphoma

    PubMed Central

    Chang, Ellen T.; Ambinder, Richard F.; Lennette, Evelyne T.; Rubertone, Mark V.; Mann, Risa B.; Borowitz, Michael; Weir, Edward G.; Abbondanzo, Susan L.; Mueller, Nancy E.

    2012-01-01

    An altered anti–Epstein-Barr virus (EBV) serologic profile preceding diagnosis is associated with an increased risk of Hodgkin lymphoma. It is unknown whether this atypical pattern predicts Hodgkin lymphoma risk further subdivided by determination of EBV in tumor cells. A nested case-control study of 128 incident Hodgkin lymphoma cases and 368 matched controls from active-duty military personnel with archived serum in the US Department of Defense Serum Repository was conducted to determine whether a panel of anti-EBV antibody titers differed in EBV+ and EBV− Hodgkin lymphoma. Among 40 EBV+ Hodgkin lymphoma cases and matched controls, statistically significant increased risks were associated with elevated anti-EBV VCA IgG antibody titers (relative risk = 3.1; 95% confidence interval [CI], 1.1-8.7), and an anti–EBNA-1/anti–EBNA-2 antibody ratio ≤ 1.0 versus > 1.0 (relative risk = 4.7; 95% CI, 1.6-13.8). In contrast, no significant associations were found among 88 EBV− Hodgkin lymphoma cases relative to their matched controls. In case-case analysis, EBV+ disease was significantly associated with a low anti–EBNA-1/anti–EBNA-2 antibody ratio. This distinc-tive serologic response to EBV latent antigens, indicative of immune dysfunction in other clinical settings, is associated with an increased risk of developing EBV+ but not EBV− Hodgkin lymphoma. PMID:22972983

  2. Histone deacetylase inhibitor romidepsin induces efficient tumor cell lysis via selective down-regulation of LMP1 and c-myc expression in EBV-positive diffuse large B-cell lymphoma.

    PubMed

    Shin, Dong-Yeop; Kim, Areumnuri; Kang, Hye Jin; Park, Sunhoo; Kim, Dong Wan; Lee, Seung-Sook

    2015-08-10

    We investigated the role of the histone deacetylase inhibitor, romidepsin, in Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL), an aggressive non-Hodgkin lymphoma with poor clinical outcomes. We used EBV-positive and EBV-negative DLBCL cell lines and generated two EBV-transfected cell lines, LY7/EBV and U2932/EBV. Romidepsin was cytotoxic to cultured EBV-positive cells via the activation of the caspase cascade. Moreover, in vivo mice xenograft models demonstrated the cytotoxicity of romidepsin to EBV-positive DLBCL cells. Romidepsin induced cytotoxicity via the reduction of LMP1 and c-myc expression in EBV-positive cells. Inhibiting either LMP1 or c-myc using small inhibitory RNAs caused partial cytotoxicity in EBV-positive Farage and U2932/EBV lines. The dual inhibition of LMP1 and c-myc showed a synergistic cytotoxic effect in EBV-positive cells similar in magnitude to that of romidepsin alone. In addition, either double blockade of LMP1 and c-myc activity or romidepsin single treatment activated EBV lytic cycle in EBV-positive cells. In conclusion, romidepsin exerts strong anti-tumor activity in EBV-positive DLBCL via the inhibition of both LMP1 and c-myc. Our findings indicate that romidepsin might be a promising treatment for EBV-positive DLBCL.

  3. Role of EBNA-3 Family Proteins in EBV Associated B-cell Lymphomagenesis

    PubMed Central

    Bhattacharjee, Shaoni; Ghosh Roy, Shatadru; Bose, Priyanka; Saha, Abhik

    2016-01-01

    Epstein-Barr virus (EBV) is highly ubiquitous in human population and establishes a lifelong asymptomatic infection within the infected host unless the immune system is compromised. Following initial infection in the oropharyngeal epithelial cells, EBV primarily infects naive B-lymphocytes and develops a number of B-cell lymphomas particularly in immune-deficient individuals. In vitro, EBV can also infect and subsequently transform quiescent B-lymphocytes into continuously proliferating lymphoblastoid cell lines (LCLs) resembling EBV-induced lymphoproliferative disorders in which a subset of latent transcripts are detected. Genetic studies revealed that EBNA-3 family comprising of three adjacent genes in the viral genome—EBNA-3A and -3C, but not -3B, are critical for B-cell transformation. Nevertheless, all three proteins appear to significantly contribute to maintain the overall proliferation and viability of transformed cells, suggesting a critical role in lymphoma development. Apart from functioning as important viral transcriptional regulators, EBNA-3 proteins associate with many cellular proteins in different signaling networks, providing a suitable platform for lifelong survival of the virus and concurrent lymphoma development in the infected host. The chapter describes the function of each these EBV nuclear antigen 3 proteins employed by the virus as a means to understand viral pathogenesis of several EBV-associated B-cell malignancies. PMID:27092119

  4. EBV-associated post-transplant lymphoproliferative disorder after umbilical cord blood transplantation in adults with hematological diseases.

    PubMed

    Sanz, J; Arango, M; Senent, L; Jarque, I; Montesinos, P; Sempere, A; Lorenzo, I; Martín, G; Moscardó, F; Mayordomo, E; Salavert, M; Cañigral, C; Boluda, B; Salazar, C; López-Hontangas, J L; Sanz, M A; Sanz, G F

    2014-03-01

    We analyzed the incidence, clinicopathological features, risk factors and prognosis of patients with EBV-associated post-transplant lymphoproliferative disorder (EBV-PTLD) in 288 adults undergoing umbilical cord blood transplantation (UCBT) at a single institution. Twelve patients developed proven EBV-PTLD at a median time of 73 days (range, 36-812). Three-year cumulative incidence (CI) of EBV-PTLD was 4.3% (95% CI: 1.9-6.7). All patients presented with extranodal involvement. Most frequently affected sites were the liver, spleen, central nervous system (CNS), Waldeyer's ring and BM in 7, 6, 4, 3 and 3 patients, respectively. One patient had polymorphic and 11 had monomorphic EBV-PTLD (7 diffuse large B-cell lymphomas not otherwise specified, 4 plasmablastic lymphomas). We confirmed donor origin and EBV infection in all histological samples. EBV-PTLD was the cause of death in 11 patients at a median time of 23 days (range, 1-84). The 3-year CI of EBV-PTLD was 12.9% (95% CI: 3.2-22.5) and 2.6% (95% CI: 0.5-4.7) for patients receiving reduced-intensity conditioning (RIC) and myeloablative conditioning, respectively (P<0.0001). In conclusion, adults with EBV-PTLD after UCBT showed frequent visceral and CNS involvement. The prognosis was poor despite routine viral monitoring and early intervention. An increased risk of EBV-PTLD was noted among recipients of RIC regimens.

  5. Modulation of B-cell exosome proteins by gamma herpesvirus infection

    PubMed Central

    Meckes, David G.; Gunawardena, Harsha P.; Dekroon, Robert M.; Heaton, Phillip R.; Edwards, Rachel H.; Ozgur, Sezgin; Griffith, Jack D.; Damania, Blossom; Raab-Traub, Nancy

    2013-01-01

    The human gamma herpesviruses, Kaposi sarcoma-associated virus (KSHV) and EBV, are associated with multiple cancers. Recent evidence suggests that EBV and possibly other viruses can manipulate the tumor microenvironment through the secretion of specific viral and cellular components into exosomes, small endocytically derived vesicles that are released from cells. Exosomes produced by EBV-infected nasopharyngeal carcinoma cells contain high levels of the viral oncogene latent membrane protein 1 and viral microRNAs that activate critical signaling pathways in recipient cells. In this study, to determine the effects of EBV and KSHV on exosome content, quantitative proteomics techniques were performed on exosomes purified from 11 B-cell lines that are uninfected, infected with EBV or with KSHV, or infected with both viruses. Using mass spectrometry, 871 proteins were identified, of which ∼360 were unique to the viral exosomes. Analysis by 2D difference gel electrophoresis and spectral counting identified multiple significant changes compared with the uninfected control cells and between viral groups. These data predict that both EBV and KSHV exosomes likely modulate cell death and survival, ribosome function, protein synthesis, and mammalian target of rapamycin signaling. Distinct viral-specific effects on exosomes suggest that KSHV exosomes would affect cellular metabolism, whereas EBV exosomes would activate cellular signaling mediated through integrins, actin, IFN, and NFκB. The changes in exosome content identified in this study suggest ways that these oncogenic viruses modulate the tumor microenvironment and may provide diagnostic markers specific for EBV and KSHV associated malignancies. PMID:23818640

  6. Anti-TNFα therapy for inflammatory bowel diseases is associated with Epstein-Barr virus lytic activation.

    PubMed

    Lapsia, Sameer; Koganti, Siva; Spadaro, Salvatore; Rajapakse, Ramona; Chawla, Anupama; Bhaduri-McIntosh, Sumita

    2016-02-01

    Anti-TNFα therapy, known to suppress T-cell immunity, is increasingly gaining popularity for treatment of autoimmune diseases including inflammatory bowel diseases (IBD). T-cell suppression increases the risk of B-cell EBV-lymphoproliferative diseases and lymphomas. Since EBV-lytic activation is essential for development of EBV-lymphomas and there have been reports of EBV-lymphomas in patients treated with anti-TNFα therapy, we investigated if patients treated with anti-TNFα antibodies demonstrate greater EBV-lytic activity in blood. Peripheral blood mononuclear cells from 10 IBD patients solely on anti-TNFα therapy compared to 3 control groups (10 IBD patients not on immunosuppressive therapy, 10 patients with abdominal pain but without IBD, and 10 healthy subjects) were examined for the percentage of T-cells, EBV load and EBV-lytic transcripts. Patients on anti-TNFα therapy had significantly fewer T-cells, greater EBV load, and increased levels of transcripts from EBV-lytic genes of all kinetic classes compared to controls. Furthermore, exposure of EBV-infected B-cell lines to anti-TNFα antibodies resulted in increased levels of BZLF1 mRNA; BZLF1 encodes for ZEBRA, the viral latency-to-lytic cycle switch. Thus, IBD patients treated with anti-TNFα antibodies have greater EBV loads likely due to enhanced EBV-lytic gene expression and anti-TNFα antibodies may be sufficient to activate the EBV lytic cycle. Findings from this pilot study lay the groundwork for additional scientific and clinical investigation into the effects of anti-TNFα therapy on the life cycle of EBV, a ubiquitous oncovirus that causes lymphomas in the setting of immunocompromise. PMID:26307954

  7. Anti-TNFα therapy for inflammatory bowel diseases is associated with Epstein-Barr virus lytic activation.

    PubMed

    Lapsia, Sameer; Koganti, Siva; Spadaro, Salvatore; Rajapakse, Ramona; Chawla, Anupama; Bhaduri-McIntosh, Sumita

    2016-02-01

    Anti-TNFα therapy, known to suppress T-cell immunity, is increasingly gaining popularity for treatment of autoimmune diseases including inflammatory bowel diseases (IBD). T-cell suppression increases the risk of B-cell EBV-lymphoproliferative diseases and lymphomas. Since EBV-lytic activation is essential for development of EBV-lymphomas and there have been reports of EBV-lymphomas in patients treated with anti-TNFα therapy, we investigated if patients treated with anti-TNFα antibodies demonstrate greater EBV-lytic activity in blood. Peripheral blood mononuclear cells from 10 IBD patients solely on anti-TNFα therapy compared to 3 control groups (10 IBD patients not on immunosuppressive therapy, 10 patients with abdominal pain but without IBD, and 10 healthy subjects) were examined for the percentage of T-cells, EBV load and EBV-lytic transcripts. Patients on anti-TNFα therapy had significantly fewer T-cells, greater EBV load, and increased levels of transcripts from EBV-lytic genes of all kinetic classes compared to controls. Furthermore, exposure of EBV-infected B-cell lines to anti-TNFα antibodies resulted in increased levels of BZLF1 mRNA; BZLF1 encodes for ZEBRA, the viral latency-to-lytic cycle switch. Thus, IBD patients treated with anti-TNFα antibodies have greater EBV loads likely due to enhanced EBV-lytic gene expression and anti-TNFα antibodies may be sufficient to activate the EBV lytic cycle. Findings from this pilot study lay the groundwork for additional scientific and clinical investigation into the effects of anti-TNFα therapy on the life cycle of EBV, a ubiquitous oncovirus that causes lymphomas in the setting of immunocompromise.

  8. An EBV recombinant deleted for residues 130-159 in EBNA3C can deregulate p53/Mdm2 and Cyclin D1/CDK6 which results in apoptosis and reduced cell proliferation

    PubMed Central

    El-Naccache, Darine W.; Robertson, Erle S.

    2016-01-01

    Epstein-Barr virus (EBV), a gamma herpes virus is associated with B-cell malignancies. EBNA-3C is critical for in vitro primary B-cell transformation. Interestingly, the N terminal domain of EBNA3C which contains residues 130–159, interacts with various cellular proteins, such as p53, Mdm2, CyclinD1/Cdk6 complex, and E2F1. In the current reverse genetics study, we deleted the residues 130-159 aa within EBNA3C open reading frame (ORF) by BACmid recombinant engineering methodology. Our experiments demonstrated that deletion of the 130-159 aa showed a reduction in cell proliferation. Also, this recombinant virus showed with higher infectivity of human peripheral blood mononuclear cells (PBMCs) compared to wild type EBV. PBMCs- infected with recombinant EBV deleted for 130-159 residues have differential expression patterns for the p53/Mdm2, CyclinD1/Cdk6 and pRb/E2F1 pathways compared to wild type EBV-infected PBMCs. PBMCs infected with recombinant virus showed increased apoptotic cell death which further resulted in activation of polymerase 1 (PARP1), an important contributor to apoptotic signaling. Interestingly, cells infected with this recombinant virus showed a dramatic decrease in chromosomal instability, indicated by the presence of increased multinucleation and micronucleation. In addition infection with recombinant virus have increased cells in G0/G1 phase and decreased cells in S-G2M phase when compared to wild type infected cells. Thus, these differences in signaling activities due to 29 amino acid residues of EBNA3C is of particular significance in deregulation of cell proliferation in EBV-infected cells. PMID:26908453

  9. Luteolin inhibits Epstein-Barr virus lytic reactivation by repressing the promoter activities of immediate-early genes.

    PubMed

    Wu, Chung-Chun; Fang, Chih-Yeu; Hsu, Hui-Yu; Chen, Yen-Ju; Chou, Sheng-Ping; Huang, Sheng-Yen; Cheng, Yu-Jhen; Lin, Su-Fang; Chang, Yao; Tsai, Ching-Hwa; Chen, Jen-Yang

    2016-08-01

    The lytic reactivation of Epstein-Barr virus (EBV) has been reported to be strongly associated with several human diseases, including nasopharyngeal carcinoma (NPC). Inhibition of the EBV lytic cycle has been shown to be of great benefit in the treatment of EBV-associated diseases. The administration of dietary compounds is safer and more convenient than other approaches to preventing EBV reactivation. We screened several dietary compounds for their ability to inhibit EBV reactivation in NPC cells. Among them, the flavonoid luteolin showed significant inhibition of EBV reactivation. Luteolin inhibited protein expression from EBV lytic genes in EBV-positive epithelial and B cell lines. It also reduced the numbers of EBV-reactivating cells detected by immunofluorescence analysis and reduced the production of virion. Furthermore, luteolin reduced the activities of the promoters of the immediate-early genes Zta (Zp) and Rta (Rp) and also inhibited Sp1-luc activity, suggesting that disruption of Sp1 binding is involved in the inhibitory mechanism. CHIP analysis revealed that luteolin suppressed the activities of Zp and Rp by deregulating Sp1 binding. Taken together, luteolin inhibits EBV reactivation by repressing the promoter activities of Zp and Rp, suggesting luteolin is a potential dietary compound for prevention of virus infection.

  10. Antibody producing B lineage cells invade the central nervous system predominantly at the time of and triggered by acute Epstein-Barr virus infection: A hypothesis on the origin of intrathecal immunoglobulin synthesis in multiple sclerosis.

    PubMed

    Otto, Carolin; Hofmann, Jörg; Ruprecht, Klemens

    2016-06-01

    Patients with multiple sclerosis (MS), a chronic inflammatory disease of the central nervous system (CNS), typically have an intrathecal synthesis of immunoglobulin (Ig)G. Intrathecal IgG is produced by B lineage cells that entered the CNS, but why and when these cells invade the CNS of patients with MS is unknown. The intrathecal IgG response in patients with MS is polyspecific and part of it is directed against different common viruses (e.g. measles virus, rubella virus, varicella zoster virus). Strong and consistent evidence suggests an association of MS and Epstein-Barr virus (EBV) infection and EBV seroprevalence in patients with MS is practically 100%. However, intriguingly, despite of the universal EBV seroprevalence, the frequency of intrathecally produced IgG to EBV in patients with MS is much lower than that of intrathecally produced IgG to other common viruses. The acute phase of primary EBV infection is characterized by a strong polyclonal B cell activation. As typical for humoral immune responses against viruses, EBV specific IgG is produced only with a temporal delay after acute EBV infection. Aiming to put the above facts into a logical structure, we here propose the hypothesis that in individuals going on to develop MS antibody producing B lineage cells invade the CNS predominantly at the time of and triggered by acute primary EBV infection. Because at the time of acute EBV infection EBV IgG producing B lineage cells have not yet occurred, the hypothesis could explain the universal EBV seroprevalence and the low frequency of intrathecally produced IgG to EBV in patients with MS. Evidence supporting the hypothesis could be provided by large prospective follow-up studies of individuals with symptomatic primary EBV infection (infectious mononucleosis). Furthermore, the clarification of the molecular mechanism underlying an EBV induced invasion of B lineage cells into the CNS of individuals going on to develop MS could corroborate it, too. If true, our

  11. Human Epstein-Barr virus (EBV)-specific cytotoxic T lymphocytes home preferentially to and induce selective regressions of autologous EBV- induced B cell lymphoproliferations in xenografted C.B-17 scid/scid mice [published erratum appears in J Exp Med 1996 Sep 1;184(3):1199

    PubMed Central

    1996-01-01

    C.B-17 scid/scid (severe combined immunodeficiency [SCID]) mice inoculated with peripheral blood lymphocytes from Epstein-Barr virus (EBV)-seropositive donors, or with EBV-transformed lymphoblastoid B cell lines (EBV-LCL), develop lethal human EBV+ B cell lymphoproliferative disorders (EBV-LPD) with characteristics similar to those arising in immunodeficient patients. Using this model, we examined the capacity of human effector cells to control human EBV-LPD. SCID mice received rabbit anti-asialo GM1 antiserum to abrogate endogenous natural killer-cell function. Preliminary experiments showed that adoptive transfer of peripheral blood mononuclear cells (PBMC), purified T cells, interleukin (IL) 2-activated PBMC or anti-CD3- activated T cells derived from EBV-seropositive donors did not result in improved survival of treated mice (in vivo effector/target ratio 2:1 to 1:1). In contrast, EBV-specific cytotoxic T lymphocytes (CTL), derived from EBV-seropositive donors and expanded in vitro, exhibited strong EBV-specific and HLA-restricted activity both in vitro and in vivo. SCID mice inoculated intraperitoneally with autologous but not with HLA-mismatched EBV-LCL had significantly improved survival relative to untreated mice after inoculation of EBV-specific CTL either intraperitoneally (P<0.001) or intravenously (P<0.001) (in vivo effector/target ratio 1:1). SCID mice bearing large subcutaneous EBV+ tumors and treated intravenously with 10(7) EBV-specific CTL achieved complete tumor regression. Both CTL- and CTL-plus-IL-2-treated mice survived significantly longer than untreated animals or animals treated with IL-2 alone (P = 0.0004 and P<0.02, respectively). SCID mice bearing two subcutaneous EBV+ tumors, one autologous and the other HLA mismatched to the EBV-specific CTL donor, had regression of only the autologous tumor after intravenous infusion of 10(7) EBV-specific CTL. Moreover, we could demonstrate preferential homing of PKH26-labeled EBV- specific CTL to

  12. Epstein-Barr virus and human immunodeficiency virus serological responses and viral burdens in HIV-infected patients treated with HAART

    NASA Technical Reports Server (NTRS)

    O'Sullivan, Cathal E.; Peng, RongSheng; Cole, Kelly Stefano; Montelaro, Ronald C.; Sturgeon, Timothy; Jenson, Hal B.; Ling, Paul D.; Butel, J. S. (Principal Investigator)

    2002-01-01

    Epstein-Barr virus (EBV) associated non-Hodgkin lymphoma is recognized as a complication of human immunodeficiency virus (HIV) infection. Little is known regarding the influence of highly active antiretroviral therapy (HAART) on the biology of EBV in this population. To characterize the EBV- and HIV-specific serological responses together with EBV DNA levels in a cohort of HIV-infected adults treated with HAART, a study was conducted to compare EBV and HIV serologies and EBV DNA copy number (DNAemia) over a 12-month period after the commencement of HAART. All patients were seropositive for EBV at baseline. Approximately 50% of patients had detectable EBV DNA at baseline, and 27/30 had detectable EBV DNA at some point over the follow-up period of 1 year. Changes in EBV DNA copy number over time for any individual were unpredictable. Significant increases in the levels of Epstein-Barr nuclear antigen (EBNA) and Epstein-Barr early antigen (EA) antibodies were demonstrated in the 17 patients who had a good response to HAART. Of 29 patients with paired samples tested, four-fold or greater increases in titers were detected for EA in 12/29 (41%), for EBNA in 7/29 (24%), for VCA-IgG in 4/29 (14%); four-fold decreases in titers were detected in 2/29 (7%) for EA and 12/29 (41%) for EBNA. A significant decline in the titer of anti-HIV antibodies was also demonstrated. It was concluded that patients with advanced HIV infection who respond to HAART have an increase in their EBV specific antibodies and a decrease in their HIV-specific antibodies. For the cohort overall, there was a transient increase in EBV DNA levels that had declined by 12 months. Copyright 2002 Wiley-Liss, Inc.

  13. Whole blood EBV-DNA predicts outcome in diffuse large B-cell lymphoma.

    PubMed

    Tisi, Maria Chiara; Cupelli, Elisa; Santangelo, Rosaria; Maiolo, Elena; Alma, Eleonora; Giachelia, Manuela; Martini, Maurizio; Bellesi, Silvia; D'Alò, Francesco; Voso, Maria Teresa; Pompili, Maurizio; Leone, Giuseppe; Larocca, Luigi Maria; Hohaus, Stefan

    2016-01-01

    An association between Epstein-Barr Virus (EBV) infection and lymphoproliferative diseases has been reported with EBV + diffuse large B cell-lymphoma (DLBCL) of the elderly described as a distinct entity. In a cohort of 218 human immunodeficiency virus (HIV)-negative patients with diffuse large B-cell lymphomas, we detected EBV-DNA in 25% of whole blood (WB) samples at diagnosis. Presence and viral load in WB, mononuclear cells or plasma did not predict the presence of EBV in the tumor biopsy. Positive Hepatitis C virus (HCV) serology was associated with a higher frequency of EBV in WB. Patients with EBV-DNA in WB had a significantly shorter progression-free (p = 0.02) and overall survival (p = 0.05) after immunochemotherapy with R-CHOP (Rituximab, Cyclophosphamide, Doxorubicin, Vincristine, Prednisolone). We conclude that detection of EBV in WB is not a surrogate marker for EBV-association in diffuse large B-cell lymphoma, however it associates with worse outcome.

  14. The Epstein-Barr Virus (EBV) in T Cell and NK Cell Lymphomas: Time for a Reassessment

    PubMed Central

    Gru, A. A.; Haverkos, B. H.; Freud, A. G.; Hastings, J.; Nowacki, N. B.; Barrionuevo, C.; Vigil, C. E.; Rochford, R.; Natkunam, Y.; Baiocchi, R. A.

    2015-01-01

    While Epstein-Barr virus (EBV) was initially discovered and characterized as an oncogenic virus in B cell neoplasms, it also plays a complex and multifaceted role in T/NK cell lymphomas. In B cell lymphomas, EBV-encoded proteins have been shown to directly promote immortalization and proliferation through stimulation of the NF-κB pathway and increased expression of anti-apoptotic genes. In the context of mature T/NK lymphomas (MTNKL), with the possible exception on extranodal NK/T cell lymphoma (ENKTL), the virus likely plays a more diverse and nuanced role. EBV has been shown to shape the tumor microenvironment by promoting Th2-skewed T cell responses and by increasing the expression of the immune checkpoint ligand PD-L1. The type of cell infected, the amount of plasma EBV DNA, and the degree of viral lytic replication have all been proposed to have prognostic value in T/NK cell lymphomas. Latency patterns of EBV infection have been defined using EBV-infected B cell models and have not been definitively established in T/NK cell lymphomas. Identifying the expression profile of EBV lytic proteins could allow for individualized therapy with the use of antiviral medications. More work needs to be done to determine whether EBV-associated MTNKL have distinct biological and clinical features, which can be leveraged for risk stratification, disease monitoring, and therapeutic purposes. PMID:26449716

  15. Neurological complications of acute and persistent Epstein-Barr virus infection in paediatric patients.

    PubMed

    Häusler, Martin; Ramaekers, Vincent Thomas; Doenges, Martin; Schweizer, Klaus; Ritter, Klaus; Schaade, Lars

    2002-10-01

    Neurological complications of Epstein-Barr virus (EBV) have been reported almost exclusively in the course of acute primary infections. The role of EBV in paediatric neurological disease was investigated prospectively over a 2-year period, searching for acute primary, chronic, and reactivated EBV infections. Active EBV infections were diagnosed in 10/48 patients, including two with acute primary EBV infections (cranial neuritis and cerebellitis), one with chronic active infection (T/NK cell lymphoma with cranial neuritis), and seven with reactivated infections. Among these seven patients, three showed "Alice in Wonderland" syndrome, one facial nerve palsy, one progressive macrocephaly, and two prolonged encephalitic illness. The prognosis was good except for the patient with lethal T/NK cell lymphoma and the two girls with encephalitic illness. Despite steroid treatment, these girls suffered prolonged cognitive impairment and epileptic seizures. Both developed left-sided hippocampal atrophy, and one of them hippocampal sclerosis. Like primary infections, reactivated EBV infections cause neurological complications in a considerable number of paediatric patients, lead to serious long-term complications, and may contribute to the pathogenesis of hippocampal lesions. PMID:12210416

  16. Prognostic impact of Epstein-Barr virus (EBV)-DNA copy number at diagnosis in chronic lymphocytic leukemia

    PubMed Central

    Xia, Yi; Gale, Robert Peter; Chen, Rui-Ze; Yang, Yu-Qiong; Wang, Li; Qu, Xiao-Yan; Qiu, Hai-Rong; Cao, Lei; Hong, Min; Wang, Rong; Wang, Yan; Fan, Lei; Chen, Yao-Yu; Hu, Zhi-Bin; Li, Jian-Yong; Xu, Wei

    2016-01-01

    Epstein-Barr virus (EBV)-DNA is detected in the blood of some persons with chronic lymphocytic leukemia (CLL) at diagnosis. Whether this is important in the development or progression of CLL is controversial. We interrogated associations between blood EBV-DNA copy number and biological and clinical variables in 243 new-diagnosed consecutive subjects with CLL. Quantification of EBV-DNA copies was done by real-time quantitative PCR (RQ-PCR). All subjects had serological evidence of prior EBV-infection. However, only 24 subjects (10%) had a EBV-DNA-positive test at diagnosis. EBV-DNA-positive subjects at diagnosis had lower hemoglobin concentrations and platelet levels, higher thymidine kinase-1 and serum ferritin levels, un-mutated IGHV genes and a greater risk of Richter transformation compared with EBV-DNA-negative subjects. Percent CD20-, CD148- and ZAP70-positive cells and mean fluorescence intensity (MFI) of each cluster designation were also increased in EBV-DNA-positive subjects at diagnosis. EBV-DNA test positivity was associated with a briefer time-to-treatment interval (HR 1.85; [95% confidence interval, 1.13, 3.03]; P=0.014) and worse survival (HR 2.77; [1.18, 6.49]; P=0.019). Reduction in EBV copies was significantly associated with therapy-response. A positive blood EBV-DNA test at diagnosis and sequential testing of EBV copies during therapy were significantly associated with biological and clinical variables, time-to-treatment, therapy-response and survival. If validated these data may be added to CLL prognostic scoring systems. PMID:26539641

  17. Downregulation of ATOH8 induced by EBV-encoded LMP1 contributes to the malignant phenotype of nasopharyngeal carcinoma

    PubMed Central

    Yan, Min; Wang, Jing; Wang, Xi; Zhang, Jialiang; Zhang, Yan; Li, Pengfei; Lei, Xinxing; Huang, Qitao; Lin, Suxia; Guo, Xiang; Liu, Quentin

    2016-01-01

    Mechanism for the malignant phenotype of nasopharyngeal carcinoma (NPC) remains poorly understood. Epstein-Barr virus (EBV) consistently appears in nearly all malignant NPC patient samples, suggesting the strong etiological link between the malignant phenotype and EBV infection. Here we found that the EBV-encoded latent membrane protein (LMP1) enhanced cell growth, motility, invasion and xenograft tumor growth of NPC. RNA-seq profiling analysis of LMP1-positive NPC patient tissues indicated that widespread gene repression contributed to malignant phenotype of NPC. The transcription factor binding site (TFBS) enrichment analysis indicated a subset of transcription factors including ATOH8, a novel transcript factor which belongs to the basic helix-loop-helix (bHLH) gene family inversely enriched in promoters of up-regulated genes and down-regulated genes. Importantly, the expression of ATOH8 was suppressed in both immortalized normal nasopharyngeal epithelial cells (NPEC) and NPC cells with LMP1 overexpression. The Real-Time PCR and Western Blot assays indicated that ATOH8 decreased expression in NPC cell lines and patient samples. Moreover, by gain- or loss-of-function assays, we demonstrated that ATOH8 inhibition promoted malignant phenotype, whereas ATOH8 restoration reversed malignant phenotype of NPC. Finally, we demonstrated that LMP1 inhibited ATOH8 expression by epigenetically impairing the occupancy of activating H3K4me3 and enhancing the occupancy of repressive H3K27me3 on ATOH8 promoter. Collectively, our study uncovered the occurrence of malignant phenotype of NPC induced by EBV infection and characterized a novel bHLH transcription factor ATOH8 as a new downstream target of LMP1. PMID:27049918

  18. Latent Expression of the Epstein-Barr Virus (EBV)-Encoded Major Histocompatibility Complex Class I TAP Inhibitor, BNLF2a, in EBV-Positive Gastric Carcinomas

    PubMed Central

    Strong, Michael J.; Laskow, Thomas; Nakhoul, Hani; Blanchard, Eugene; Liu, Yaozhong; Wang, Xia; Baddoo, Melody; Lin, Zhen; Yin, Qinyan

    2015-01-01

    The Epstein-Barr virus (EBV) BNLF2a gene product provides immune evasion properties to infected cells through inhibition of transporter associated with antigen processing (TAP)-mediated transport of antigen peptides. Although BNLF2a is considered to be a lytic gene, we demonstrate that it is expressed in nearly half of the EBV-associated gastric carcinomas analyzed. Further, we show that BNLF2a expression is dissociated from lytic gene expression. BNLF2a is therefore expressed in this latency setting, potentially helping protect the infected tumor cells from immunosurveillance. PMID:26178981

  19. Purified recombinant EBV desoxyribonuclease in serological diagnosis of nasopharyngeal carcinoma.

    PubMed

    Stolzenberg, M C; Debouze, S; Ng, M; Sham, J; Choy, D; Bouguermouh, A; Chan, K H; Ooka, T

    1996-05-01

    To evaluate applications of highly purified recombinant EBV DNAase in the diagnosis and prognosis of NPC, we tested sera from patients with NPC, other EBV-associated diseases and EBV-seropositive and -seronegative healthy subjects by immunoblotting and DNAase inhibitory assay. The results were compared with those obtained by the conventional immunofluorescence assays against the EBV-specified early antigens and capsid antigens. The antigenic specificity of the immunoblotting assay for IgG antibody against the viral enzyme, but not that for the IgA antibody, was correlated with DNAase-inhibitory activity of the sera and their titers of IgG antibodies against the viral early antigens. Purified IgA as well as IgG from NPC sera inhibited enzyme activity with similar efficiency. The use of highly purified viral DNase has increased the sensitivity of detection of the corresponding antibodies by immunoblotting, with the IgG antibody being detected in all but one, and IgA antibody in all but 2, of the 174 NPC sera tested. The IgG antibody was also commonly detected in the other groups of control sera, while the IgA antibody was detected in about 10% of African Burkitt's lymphoma and Algerian Hodgkin's lymphoma patients and less than 3% of the other control subjects. These results suggest that IgA antibody against recombinant EBV DNAase may be useful in the diagnosis of NPC, but the level of this antibody did not appear to be related to clinical stages of this cancer. PMID:8621254

  20. Spironolactone blocks Epstein-Barr virus production by inhibiting EBV SM protein function.

    PubMed

    Verma, Dinesh; Thompson, Jacob; Swaminathan, Sankar

    2016-03-29

    Clinically available drugs active against Epstein-Barr virus (EBV) and other human herpesviruses are limited to those targeting viral DNA replication. To identify compounds directed against other steps in the viral life cycle, we searched for drugs active against the EBV SM protein, which is essential for infectious virus production. SM has a highly gene-specific mode of action and preferentially enhances expression of several late lytic cycle EBV genes. Here we demonstrate that spironolactone, a mineralocorticoid receptor antagonist approved for clinical use, inhibits SM function and infectious EBV production. Expression of EBV viral capsid antigen is highly SM dependent, and spironolactone inhibits viral capsid antigen synthesis and capsid formation, blocking EBV virion production at a step subsequent to viral DNA replication. In addition, spironolactone inhibits expression of other SM-dependent genes necessary for infectious virion formation. We further demonstrate that molecules structurally related to spironolactone with similar antimineralocorticoid blocking activity do not inhibit EBV production. These findings pave the way for development of antiherpesvirus drugs with new mechanisms of action directed against SM and homologous essential proteins in other herpesviruses. PMID:26976570

  1. Spironolactone blocks Epstein-Barr virus production by inhibiting EBV SM protein function.

    PubMed

    Verma, Dinesh; Thompson, Jacob; Swaminathan, Sankar

    2016-03-29

    Clinically available drugs active against Epstein-Barr virus (EBV) and other human herpesviruses are limited to those targeting viral DNA replication. To identify compounds directed against other steps in the viral life cycle, we searched for drugs active against the EBV SM protein, which is essential for infectious virus production. SM has a highly gene-specific mode of action and preferentially enhances expression of several late lytic cycle EBV genes. Here we demonstrate that spironolactone, a mineralocorticoid receptor antagonist approved for clinical use, inhibits SM function and infectious EBV production. Expression of EBV viral capsid antigen is highly SM dependent, and spironolactone inhibits viral capsid antigen synthesis and capsid formation, blocking EBV virion production at a step subsequent to viral DNA replication. In addition, spironolactone inhibits expression of other SM-dependent genes necessary for infectious virion formation. We further demonstrate that molecules structurally related to spironolactone with similar antimineralocorticoid blocking activity do not inhibit EBV production. These findings pave the way for development of antiherpesvirus drugs with new mechanisms of action directed against SM and homologous essential proteins in other herpesviruses.

  2. Spironolactone blocks Epstein–Barr virus production by inhibiting EBV SM protein function

    PubMed Central

    Verma, Dinesh; Thompson, Jacob; Swaminathan, Sankar

    2016-01-01

    Clinically available drugs active against Epstein–Barr virus (EBV) and other human herpesviruses are limited to those targeting viral DNA replication. To identify compounds directed against other steps in the viral life cycle, we searched for drugs active against the EBV SM protein, which is essential for infectious virus production. SM has a highly gene-specific mode of action and preferentially enhances expression of several late lytic cycle EBV genes. Here we demonstrate that spironolactone, a mineralocorticoid receptor antagonist approved for clinical use, inhibits SM function and infectious EBV production. Expression of EBV viral capsid antigen is highly SM dependent, and spironolactone inhibits viral capsid antigen synthesis and capsid formation, blocking EBV virion production at a step subsequent to viral DNA replication. In addition, spironolactone inhibits expression of other SM-dependent genes necessary for infectious virion formation. We further demonstrate that molecules structurally related to spironolactone with similar antimineralocorticoid blocking activity do not inhibit EBV production. These findings pave the way for development of antiherpesvirus drugs with new mechanisms of action directed against SM and homologous essential proteins in other herpesviruses. PMID:26976570

  3. P-glycoprotein is expressed and causes resistance to chemotherapy in EBV-positive T-cell lymphoproliferative diseases.

    PubMed

    Yoshimori, Mayumi; Takada, Honami; Imadome, Ken-Ichi; Kurata, Morito; Yamamoto, Kouhei; Koyama, Takatoshi; Shimizu, Norio; Fujiwara, Shigeyoshi; Miura, Osamu; Arai, Ayako

    2015-10-01

    Epstein-Barr virus-positive T-cell lymphoproliferative diseases (EBV-T-LPDs) are rare lymphomas with poor prognosis. Although chemotherapeutic strategies such as CHOP have been often selected, they have exhibited only limited efficacy. To clarify the mechanism of chemoresistance, we examined P-glycoprotein (P-gp) expression. P-gp acts as an energy-dependent efflux pump that excretes drugs from the cytoplasm, resulting in low-intracellular drug concentrations and poor sensitivity to chemotherapy. We examined P-gp expression in EBV-positive cells by immunohistochemistry staining in three patients of EBV-T-LPDs and the expression was detected in all patients. We also examined mdr1 mRNA expression by reverse-transcriptase polymerase-chain reaction (RT-PCR) in EBV-positive tumor cells from these patients and additional three patients. The expression was detected in all examined patients. In five EBV-T-LPDs patients, P-gp function was detected by Rhodamine-123 efflux assay in these cells. The efflux was inhibited by treatment with a P-gp inhibitor, cyclosporine A (CsA). We also examined and detected P-gp expression in EBV-positive T-cell lines SNT8 and SNT16 established from EBV-T-LPDs patients, by RT-PCR and western blotting. The function was also detected by Rhodamine-123 efflux in these cell lines. Inhibition and knock down of P-gp by CsA and siRNA, respectively, enhanced etoposide- and doxorubicin-induced cell death in the EBV-positive T-cell lines. Finally, we infected the T-cell line MOLT4 with EBV, and found that mdr1 mRNA expression and Rhodamine 123 efflux were upregulated after infection. These results indicated that enhanced P-gp expression contributed to the chemoresistance of EBV-T-LPDs.

  4. Prevention of EBV lymphoma development by oncolytic myxoma virus in a murine xenograft model of post-transplant lymphoproliferative disease

    SciTech Connect

    Kim, Manbok; Rahman, Masmudur M.; Cogle, Christopher R.

    2015-07-10

    Epstein–Barr virus (EBV) has been associated with a variety of epithelial and hematologic malignancies, including B-, T- and NK cell-lymphomas, Hodgkin's disease (HD), post-transplant lymphoproliferative diseases (LPDs), nasopharyngeal and gastric carcinomas, smooth muscle tumors, and HIV-associated lymphomas. Currently, treatment options for EBV-associated malignancies are limited. We have previously shown that myxoma virus specifically targets various human solid tumors and leukemia cells in a variety of animal models, while sparing normal human or murine tissues. Since transplant recipients of bone marrow or solid organs often develop EBV-associated post-transplant LPDs and lymphoma, myxoma virus may be of utility to prevent EBV-associated malignancies in immunocompromised transplant patients where treatment options are frequently limited. In this report, we demonstrate the safety and efficacy of myxoma virus purging as a prophylactic strategy for preventing post-transplant EBV-transformed human lymphomas, using a highly immunosuppressed mouse xenotransplantation model. This provides support for developing myxoma virus as a potential oncolytic therapy for preventing EBV-associated LPDs following transplantation of bone marrow or solid organ allografts. - Highlights: • Myxoma virus effectively infects and purges EBV lymphoma cells in vivo. • Oncolytic myxoma virus effectively eradicates oncogenic EBV tumorigenesis. • Ex vivo pre-treatment of myxoma virus can be effective as a preventive treatment modality for post-transplant lymphoproliferative diseases.

  5. Activation of the Epstein-Barr virus replicative cycle by human herpesvirus 6.

    PubMed Central

    Flamand, L; Stefanescu, I; Ablashi, D V; Menezes, J

    1993-01-01

    One common attribute of herpesviruses is the ability to establish latent, life-long infections. The role of virus-virus interaction in viral reactivation between or among herpesviruses has not been studied. Preliminary experiments in our laboratory had indicated that infection of Epstein-Barr virus (EBV) genome-positive human lymphoid cell lines with human herpesvirus 6 (HHV-6) results in EBV reactivation in these cells. To further our knowledge of this complex phenomenon, we investigated the effect of HHV-6 infection on expression of the viral lytic cycle proteins of EBV. Our results indicate that HHV-6 upregulates, by up to 10-fold, expression of the immediate-early Zebra antigen and the diffuse and restricted (85 kDa) early antigens (EA-D and EA-R, respectively) in both EBV producer and nonproducer cell lines (i.e., P3HR1, Akata, and Raji). Maximal EA-D induction was observed at 72 h post-HHV-6 infection. Furthermore, expression of late EBV gene products, namely, the viral capsid antigen (125 kDa) and viral membrane glycoprotein gp350, was also increased in EBV producer cells (P3HR1 and Akata) following infection by HHV-6. By using dual-color membrane immunofluorescence, it was found that most of the cells expressing viral membrane glycoprotein gp350 were also positive for HHV-6 antigens, suggesting a direct effect of HHV-6 replication on induction of the EBV replicative cycle. No expression of late EBV antigens was observed in Raji cells following infection by HHV-6, implying a lack of functional complementation between the deleted form of EBV found in Raji cells and the superinfecting HHV-6. The susceptibility of the cell lines to infection by HHV-6 correlated with increased expression of various EBV proteins in that B95-8 cells, which are not susceptible to HHV-6 infection, did not show an increase in expression of EBV antigens following treatment with HHV-6. Moreover, UV light-irradiated or heat-inactivated HHV-6 had no upregulating effect on the Zebra

  6. EBV-miR-BART10-3p facilitates epithelial-mesenchymal transition and promotes metastasis of nasopharyngeal carcinoma by targeting BTRC

    PubMed Central

    Yan, Qijia; Zeng, Zhaoyang; Gong, Zhaojian; Zhang, Wenling; Li, Xiayu; He, Baoyu; Song, Yali; Li, Qiao; Zeng, Yong; Liao, Qianjin; Chen, Pan; Shi, Lei; Fan, Songqing; Xiang, Bo; Ma, Jian; Zhou, Ming; Li, Xiaoling; Yang, Jianbo; Xiong, Wei; Li, Guiyuan

    2015-01-01

    Epstein-Barr virus (EBV) infection is closely associated with tumorigenesis and development of nasopharyngeal carcinoma (NPC), but the underlying molecular mechanisms remain poorly understood. It has been recently reported that EBV encodes 44 mature miRNAs, some of which were found to promote tumor development by targeting virus-infected host genes or self-viral genes. However, few targets of EBV encoded-miRNAs that are related to NPC development have been identified to date. In this study, we revealed that in NPC cells, EBV-miR-BART10-3p directly targets BTRC gene that encodes βTrCP (beta-transducin repeat containing E3 ubiquitin protein ligase). We found that EBV-miR-BART10-3p expression in clinical samples from a cohort of 106 NPC patients negatively correlated with BTRC expression levels. Over-expression of EBV-miR-BART10-3p and down-regulation of BTRC were associated with poor prognosis in NPC patients. EBV-miR-BART10-3p promoted the invasion and migration cabilities of NPC cells through the targeting of BTRC and regulation of the expression of the downstream substrates β-catenin and Snail. As a result, EBV-miR-BART10-3p facilitated epithelial-mesenchymal transition of NPC. Our study presents an unreported mechanism underlying EBV infection in NPC carcinogenesis, and provides a potential novel biomarker for NPC diagnosis, treatment and prognosis. PMID:26497204

  7. Gammaherpesvirus Infection of Human Neuronal Cells

    PubMed Central

    Jha, Hem Chandra; Mehta, Devan; Lu, Jie; El-Naccache, Darine; Shukla, Sanket K.; Kovacsics, Colleen; Kolson, Dennis

    2015-01-01

    ABSTRACT Gammaherpesviruses human herpesvirus 4 (HHV4) and HHV8 are two prominent members of the herpesvirus family associated with a number of human cancers. HHV4, also known as Epstein-Barr virus (EBV), a ubiquitous gammaherpesvirus prevalent in 90 to 95% of the human population, is clinically associated with various neurological diseases such as primary central nervous system lymphoma, multiple sclerosis, Alzheimer’s disease, cerebellar ataxia, and encephalitis. However, the possibility that EBV and Kaposi’s sarcoma-associated herpesvirus (KSHV) can directly infect neurons has been largely overlooked. This study has, for the first time, characterized EBV infection in neural cell backgrounds by using the Sh-Sy5y neuroblastoma cell line, teratocarcinoma Ntera2 neurons, and primary human fetal neurons. Furthermore, we also demonstrated KSHV infection of neural Sh-Sy5y cells. These neuronal cells were infected with green fluorescent protein-expressing recombinant EBV or KSHV. Microscopy, genetic analysis, immunofluorescence, and Western blot analyses for specific viral antigens supported and validated the infection of these cells by EBV and KSHV and showed that the infection was efficient and productive. Progeny virus produced from infected neuronal cells efficiently infected fresh neuronal cells, as well as peripheral blood mononuclear cells. Furthermore, acyclovir was effective at inhibiting the production of virus from neuronal cells similar to lymphoblastoid cell lines; this suggests active lytic replication in infected neurons in vitro. These studies represent a potentially new in vitro model of EBV- and KSHV-associated neuronal disease development and pathogenesis. PMID:26628726

  8. Epstein-Barr virus (EBV)-encoded dUTPase and chronic restraint induce impaired learning and memory and sickness responses.

    PubMed

    Aubrecht, Taryn G; Weil, Zachary M; Ariza, Maria Eugenia; Williams, Marshall; Reader, Brenda F; Glaser, Ronald; Sheridan, John F; Nelson, Randy J

    2014-10-01

    Most adult humans have been infected with Epstein-Barr virus (EBV) and carry the latent virus. The EBV genome codes for several proteins that form an early antigen complex important for viral replication; one of these proteins is deoxyuridine triphosphate nucleotidohydrolase (dUTPase). The EBV-encoded dUTPase can induce sickness responses in mice. Because stress can increase latent virus reactivation, we hypothesized that chronic restraint would exacerbate sickness behaviors elicited by EBV-encoded dUTPase. Male Swiss-Webster mice were injected daily for 15 days with either saline or EBV-encoded dUTPase. Additionally, half of the mice from each condition were either restrained for 3h daily or left undisturbed. Restraint stress impaired learning and memory in the passive avoidance chamber; impaired learning and memory was due to EBV-encoded dUTPase injected into restrained mice. EBV-encoded dUTPase induced sickness responses and restraint stress interacts with EBV-encoded dUTPase to exacerbate the sickness response. These data support a role for EBV-encoded dUTPase and restraint stress in altering the pathophysiology of EBV independent of viral replication.

  9. EBV-positive diffuse large B-cell lymphoma of the elderly: 2016 update on diagnosis, risk-stratification, and management.

    PubMed

    Castillo, Jorge J; Beltran, Brady E; Miranda, Roberto N; Young, Ken H; Chavez, Julio C; Sotomayor, Eduardo M

    2016-05-01

    Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) of the elderly is a provisional entity included in the 2008 WHO classification of lymphoid neoplasms. It is a disease typically seen in the elderly and thought to be associated with chronic EBV infection and severe immunosuppression with a component of immunosenescence. Recent research, however, has suggested that EBV-positive DLBCL can be seen in younger, immunocompetent patients. The diagnosis of EBV-positive DLBCL of the elderly is made through a careful pathological evaluation. The differential diagnosis includes infectious mononucleosis (specifically in younger patients), lymphomatoid granulomatosis, Hodgkin lymphoma, and gray zone lymphoma, among others. Detection of EBV-encoded RNA (EBER) is considered standard for diagnosis; however, a clear cutoff for positivity has not been defined. The International Prognostic Index (IPI), and the Oyama score can be used for risk-stratification. The Oyama score includes age >70 years and presence of B symptoms. The expression of CD30 is emerging as a potential adverse, and targetable, prognostic factor. Patients with EBV-positive DLBCL should be staged and managed following similar guidelines than patients with EBV-negative DLBCL. It has been suggested, however, that EBV-positive patients have a worse prognosis than EBV-negative counterparts in the era of chemoimmunotherapy. There is an opportunity to study and develop targeted therapy in the management of patients with EBV-positive DLBCL.

  10. EBV-Encoded LMP1 Upregulates Igκ 3′Enhancer Activity and Igκ Expression in Nasopharyngeal Cancer Cells by Activating the Ets-1 through ERKs Signaling

    PubMed Central

    Zheng, Hui; Hu, Duosha; Li, Ming; Tao, Yongguang; Bode, Ann M.; Dong, Zigang; Cao, Ya

    2012-01-01

    Accumulating evidence indicates that epithelial cancer cells, including nasopharyngeal carcinoma (NPC) cells, express immunoglobulins (Igs). We previously found that the expression of the kappa light chain protein in NPC cells can be upregulated by the EBV-encoded latent membrane protein 1 (LMP1). In the present study, we used NPC cell lines as models and found that LMP1-augmented kappa production corresponds with elevations in ERKs phosphorylation. PD98059 attenuates LMP1-induced ERKs phosphorylation resulting in decreased expression of the kappa light chain. ERK-specific small interfering RNA blunts LMP1-induced kappa light chain gene expression. Luciferase reporter assays demonstrate that immunoglobulin κ 3′ enhancer (3′Eκ) is active in Igκ-expressing NPC cells and LMP1 upregulates the activity of 3′Eκ in NPC cells. Moreover, mutation analysis of the PU binding site in 3′Eκ and inhibition of the MEK/ERKs pathway by PD98059 indicate that the PU site is functional and LMP1-enhanced 3′Eκ activity is partly regulated by this site. PD98059 treatment also leads to a concentration-dependent inhibition of LMP1-induced Ets-1 expression and phosphorylation, which corresponds with a dose-dependent attenuation of LMP1-induced ERK phosphorylation and kappa light chain expression. Suppression of endogenous Ets-1 by small interfering RNA is accompanied by a decrease of Ig kappa light chain expression. Gel shift assays using nuclear extracts of NPC cells indicate that the transcription factor Ets-1 is recruited by LMP1 to the PU motif within 3′Eκ in vitro. ChIP assays further demonstrate Ets-1 binding to the PU motif of 3′Eκ in cells. These results suggest that LMP1 upregulates 3′Eκ activity and kappa gene expression by activating the Ets-1 transcription factor through the ERKs signaling pathway. Our studies provide evidence for a novel regulatory mechanism of kappa expression, by which virus-encoded proteins activate the kappa 3′ enhancer through

  11. Epstein-Barr virus infection and nasopharyngeal carcinoma: the other side of the coin.

    PubMed

    Perri, Francesco; Della Vittoria Scarpati, Giuseppina; Giuliano, Mario; D'Aniello, Carmine; Gnoni, Antonio; Cavaliere, Carla; Licchetta, Antonella; Pisconti, Salvatore

    2015-11-01

    Oncogenic viruses may have a significant impact on the therapeutic management of several malignancies besides their well-known role in tumor pathogenesis. Epstein-Barr virus (EBV) induces neoplastic transformation of epithelial cells of the nasopharynx by various molecular mechanisms mostly involving activation of oncogenes and inactivation of tumor-suppressor genes. EBV infection can also induce the expression of several immunogenic peptides on the plasma membrane of the infected cells. Importantly, these virus-related antigens may be used as targets for antitumor immunotherapy-based treatment strategies. Two different immunotherapy strategies, namely adoptive and active immunotherapy, have been developed and strongly improved in the recent years. Furthermore, EBV infection may influence the use of targeted therapies for nasopharyngeal carcinoma (NPC) considering that the presence of EBV can induce important modifications in cell signaling. As an example, latent membrane protein type 1 is a viral transmembrane protein mainly involved in the cancerogenesis process, which can also mediate overexpression of the epidermal growth factor receptor (EGFR) in NPC cells, rendering them more sensitive to anti-EGFR therapy. Finally, EBV may induce epigenetic changes in the infected cells, such as DNA hypermethylation and histone deacetylation, that can sustain tumor growth and can thus be considered potential targets for novel therapies. In conclusion, EBV infection can modify important biological features of NPC cells, rendering them more vulnerable to both immunotherapy and targeted therapy.

  12. EBV-induced human CD8+ NKT cells suppress tumorigenesis by EBV-associated malignancies.

    PubMed

    Yuling, He; Ruijing, Xiao; Li, Li; Xiang, Ji; Rui, Zhou; Yujuan, Wang; Lijun, Zhang; Chunxian, Du; Xinti, Tan; Wei, Xiao; Lang, Chen; Yanping, Jiang; Tao, Xiong; Mengjun, Wu; Jie, Xiong; Youxin, Jin; Jinquan, Tan

    2009-10-15

    The underlying mechanism of the protective and suppressive role of NKT cells in human tumor immunosurveillance remains to be fully elucidated. We show that the frequencies of CD8(+) NKT cells in patients with EBV-associated Hodgkin's lymphoma or nasopharyngeal carcinoma are significantly lower than those in healthy EBV carriers. These CD8(+) NKT cells in tumor patients are also functionally impaired. In human-thymus-severe combined immunodeficient (hu-thym-SCID) chimeras, EBV challenge efficiently promotes the generation of IFN-gamma-biased CD8(+) NKT cells. These cells are strongly cytotoxic, drive syngeneic T cells into a Th1 bias, and enhance T-cell cytotoxicity to EBV-associated tumor cells. Interleukin-4-biased CD4(+) NKT cells are predominately generated in unchallenged chimeras. These cells are noncytotoxic, drive syngeneic T cells into a Th2 bias, and do not affect T-cell cytotoxicity. In humanized xenogeneic tumor-transplanted hu-thym-SCID chimeras, adoptive transfer with EBV-induced CD8(+) NKT cells significantly suppresses tumorigenesis by EBV-associated malignancies. EBV-induced CD8(+) NKT cells are necessary and sufficient to enhance the T-cell immunity to EBV-associated malignancies in the hu-thym-SCID chimeras. CD4(+) NKT cells are synergetic with CD8(+) NKT cells, leading to a more pronounced T-cell antitumor response in the chimeras cotransferred with CD4(+) and CD8(+) NKT cells. Thus, immune reconstitution with EBV-induced CD8(+) NKT cells could be a useful strategy in management of EBV-associated malignancies. PMID:19808969

  13. Hypermethylation of the tumor suppressor gene PRDM1/Blimp-1 supports a pathogenetic role in EBV-positive Burkitt lymphoma

    PubMed Central

    Zhang, T; Ma, J; Nie, K; Yan, J; Liu, Y; Bacchi, C E; Queiroga, E M; Gualco, G; Sample, J T; Orazi, A; Knowles, D M; Tam, W

    2014-01-01

    PRDM1/Blimp-1 is a tumor suppressor gene in the activated B-cell subtype of diffuse large B-cell lymphomas. Its inactivation contributes to pathogenesis in this setting by impairing terminal B-cell differentiation induced by constitutive nuclear factor-κB activation. The role of PRDM1 in Burkitt lymphoma (BL) lymphomagenesis is not known. Here we identified hypermethylation of the promoter region and exon 1 of PRDM1 in all six Epstein–Barr virus (EBV)-positive BL cell lines and 12 of 23 (52%) primary EBV-positive BL or BL-related cases examined, but in none of the EBV-negative BL cell lines or primary tumors that we assessed, implying a tumor suppressor role for PRDM1 specifically in EBV-associated BL. A direct induction of PRDM1 hypermethylation by EBV is unlikely, as PRDM1 hypermethylation was not observed in EBV-immortalized B lymphoblastoid cell lines. Treatment of EBV-positive BL cells with 5′ azacytidine resulted in PRDM1 induction associated with PRDM1 demethylation, consistent with transcriptional silencing of PRDM1 as a result of DNA methylation. Overexpression of PRDM1 in EBV-positive BL cell lines resulted in cell cycle arrest. Our results expand the spectrum of lymphoid malignancies in which PRDM1 may have a tumor suppressor role and identify an epigenetic event that likely contributes to the pathogenesis of BL. PMID:25382611

  14. Control of Cell Cycle Entry and Apoptosis in B Lymphocytes Infected by Epstein-Barr Virus

    PubMed Central

    Spender, Lindsay C.; Cannell, Emma J.; Hollyoake, Martine; Wensing, Barbara; Gawn, Jonathan M.; Brimmell, Matthew; Packham, Graham; Farrell, Paul J.

    1999-01-01

    Infection of human B cells with Epstein-Barr virus (EBV) results in activation of the cell cycle and cell growth. To interpret the mechanisms by which EBV activates the cell, we have assayed many proteins involved in control of the G0 and G1 phases of the cell cycle and regulation of apoptosis. In EBV infection most of the changes, including the early induction of cyclin D2, are dependent on expression of EBV genes, but an alteration in the E2F-4 profile was partly independent of viral gene expression, presumably occurring in response to signal transduction activated when the virus binds to its receptor, CD21. By comparing the expression of genes controlling apoptosis, including those encoding several members of the BCL-2 family of proteins, the known relative resistance of EBV-immortalized B-cell lines to apoptosis induced by low serum was found to correlate with expression of both BCL-2 and A20. A20 can be regulated by the NF-κB transcription factor, which is known to be activated by the EBV LMP-1 protein. Quantitative assays demonstrated a direct temporal relationship between LMP-1 protein levels and active NF-κB during the time course of infection. PMID:10233927

  15. Functional homology of gHs and gLs from EBV-related {gamma}-herpesviruses for EBV-induced membrane fusion

    SciTech Connect

    Omerovic, Jasmina; Longnecker, Richard . E-mail: r-longnecker@northwestern.edu

    2007-08-15

    Epstein-Barr virus (EBV) is a human {gamma}-herpesvirus that primarily infects B lymphocytes and epithelial cells. Entry of EBV into B cells requires the viral glycoproteins gp42, gH/gL and gB, while gp42 is not necessary for infection of epithelial cells. In EBV, gH and gL form two distinct complexes, a bipartite complex that contains only gH and gL, used for infection of epithelial cells, and a tripartite complex that additionally includes gp42, used for infection of B cells. The gH/gL complex is conserved within the herpesvirus family, but its exact role in entry and mechanism of fusion is not yet known. To understand more about the functionality of EBVgH/gL, we investigated the functional homology of gHs and gLs from human herpesvirus 8 (HHV8) and two primate (rhesus and marmoset) {gamma}-herpesviruses in EBV-mediated virus-free cell fusion assay. Overall, gHs and gLs from the more homologous primate herpesviruses were better at complementing EBV gH and gL in fusion than HHV8 gH and gL. Interestingly, marmoset gH was able to complement fusion with epithelial cells, but not B cells. Further investigation of this led to the discovery that EBVgH is the binding partner of gp42 in the tripartite complex and the absence of fusion with B cells in the presence of marmoset gH/gL is due to its inability to bind gp42.

  16. Molecular pathogenesis of EBV susceptibility in XLP as revealed by analysis of female carriers with heterozygous expression of SAP.

    PubMed

    Palendira, Umaimainthan; Low, Carol; Chan, Anna; Hislop, Andrew D; Ho, Edwin; Phan, Tri Giang; Deenick, Elissa; Cook, Matthew C; Riminton, D Sean; Choo, Sharon; Loh, Richard; Alvaro, Frank; Booth, Claire; Gaspar, H Bobby; Moretta, Alessandro; Khanna, Rajiv; Rickinson, Alan B; Tangye, Stuart G

    2011-11-01

    X-linked lymphoproliferative disease (XLP) is a primary immunodeficiency caused by mutations in SH2D1A which encodes SAP. SAP functions in signalling pathways elicited by the SLAM family of leukocyte receptors. A defining feature of XLP is exquisite sensitivity to infection with EBV, a B-lymphotropic virus, but not other viruses. Although previous studies have identified defects in lymphocytes from XLP patients, the unique role of SAP in controlling EBV infection remains unresolved. We describe a novel approach to this question using female XLP carriers who, due to random X-inactivation, contain both SAP(+) and SAP(-) cells. This represents the human equivalent of a mixed bone marrow chimera in mice. While memory CD8(+) T cells specific for CMV and influenza were distributed across SAP(+) and SAP(-) populations, EBV-specific cells were exclusively SAP(+). The preferential recruitment of SAP(+) cells by EBV reflected the tropism of EBV for B cells, and the requirement for SAP expression in CD8(+) T cells for them to respond to Ag-presentation by B cells, but not other cell types. The inability of SAP(-) clones to respond to Ag-presenting B cells was overcome by blocking the SLAM receptors NTB-A and 2B4, while ectopic expression of NTB-A on fibroblasts inhibited cytotoxicity of SAP(-) CD8(+) T cells, thereby demonstrating that SLAM receptors acquire inhibitory function in the absence of SAP. The innovative XLP carrier model allowed us to unravel the mechanisms underlying the unique susceptibility of XLP patients to EBV infection in the absence of a relevant animal model. We found that this reflected the nature of the Ag-presenting cell, rather than EBV itself. Our data also identified a pathological signalling pathway that could be targeted to treat patients with severe EBV infection. This system may allow the study of other human diseases where heterozygous gene expression from random X-chromosome inactivation can be exploited.

  17. Physical activity, immunity and infection.

    PubMed

    Romeo, J; Wärnberg, J; Pozo, T; Marcos, A

    2010-08-01

    During the last few decades, scientific evidence has confirmed a wide range of health benefits related to regular physical activity. How physical activity affects the immune function and infection risk is, however, still under debate. Commonly, intensive exercise suppresses the activity and levels of several immune cells, while other immune functions may be stimulated by moderate physical activity. With this knowledge, the understanding of the relationship between different levels of physical activity on the immune function has been raised as a potential tool to protect health not only in athletes but also in the general population; the mechanisms that translate a physically active lifestyle into good health continue to be investigated. Reviewing the literature, although several outcomes (i.e. the mechanisms by which different levels and duration of physical activity programmes affect numerous cell types and responses) remain unclear, given that the additional benefits encompass healthy habits including exercise, the use of physical activity programmes may result in improved health of elderly populations. Moderate physical activity or moderate-regulated training may enhance the immune function mainly in less fit subjects or sedentary population and the pre-event fitness status also seems to be an important individual factor regarding this relationship. Although adequate nutrition and regular physical activity habits may synergistically improve health, clinical trials in athletes using nutritional supplements to counteract the immune suppression have been inconclusive so far.Further research is necessary to find out to what extent physical activity training can exert an effect on the immune function.

  18. NCI International EBV-Gastric Cancer Consortium

    Cancer.gov

    A collaboration among NCI and extramural investigators, established by DCEG in 2006, that utilizes data and biospecimens from completed and ongoing case series and observational studies of gastric cancer to replicate and extend findings from previous studies hindered by small numbers of EBV-positive cases, and to stimulate multidisciplinary research in this area.

  19. EBV Nuclear Antigen 3C Mediates Regulation of E2F6 to Inhibit E2F1 Transcription and Promote Cell Proliferation.

    PubMed

    Pei, Yonggang; Banerjee, Shuvomoy; Sun, Zhiguo; Jha, Hem Chandra; Saha, Abhik; Robertson, Erle S

    2016-08-01

    Epstein-Barr virus (EBV) is considered a ubiquitous herpesvirus with the ability to cause latent infection in humans worldwide. EBV-association is evidently linked to different types of human malignancies, mainly of epithelial and lymphoid origin. Of interest is the EBV nuclear antigen 3C (EBNA3C) which is critical for EBV-mediated immortalization. Recently, EBNA3C was shown to bind the E2F1 transcription regulator. The E2F transcription factors have crucial roles in various cellular functions, including cell cycle, DNA replication, DNA repair, cell mitosis, and cell fate. Specifically, E2F6, one of the unique E2F family members, is known to be a pRb-independent transcription repressor of E2F-target genes. In our current study, we explore the role of EBNA3C in regulating E2F6 activities. We observed that EBNA3C plays an important role in inducing E2F6 expression in LCLs. Our study also shows that EBNA3C physically interacts with E2F6 at its amino and carboxy terminal domains and they form a protein complex in human cells. In addition, EBNA3C stabilizes the E2F6 protein and is co-localized in the nucleus. We also demonstrated that both EBNA3C and E2F6 contribute to reduction in E2F1 transcriptional activity. Moreover, E2F1 forms a protein complex with EBNA3C and E2F6, and EBNA3C competes with E2F1 for E2F6 binding. E2F6 is also recruited by EBNA3C to the E2F1 promoter, which is critical for EBNA3C-mediated cell proliferation. These results demonstrate a critical role for E2F family members in EBV-induced malignancies, and provide new insights for targeting E2F transcription factors in EBV-associated cancers as potential therapeutic intervention strategies. PMID:27548379

  20. EBV Nuclear Antigen 3C Mediates Regulation of E2F6 to Inhibit E2F1 Transcription and Promote Cell Proliferation.

    PubMed

    Pei, Yonggang; Banerjee, Shuvomoy; Sun, Zhiguo; Jha, Hem Chandra; Saha, Abhik; Robertson, Erle S

    2016-08-01

    Epstein-Barr virus (EBV) is considered a ubiquitous herpesvirus with the ability to cause latent infection in humans worldwide. EBV-association is evidently linked to different types of human malignancies, mainly of epithelial and lymphoid origin. Of interest is the EBV nuclear antigen 3C (EBNA3C) which is critical for EBV-mediated immortalization. Recently, EBNA3C was shown to bind the E2F1 transcription regulator. The E2F transcription factors have crucial roles in various cellular functions, including cell cycle, DNA replication, DNA repair, cell mitosis, and cell fate. Specifically, E2F6, one of the unique E2F family members, is known to be a pRb-independent transcription repressor of E2F-target genes. In our current study, we explore the role of EBNA3C in regulating E2F6 activities. We observed that EBNA3C plays an important role in inducing E2F6 expression in LCLs. Our study also shows that EBNA3C physically interacts with E2F6 at its amino and carboxy terminal domains and they form a protein complex in human cells. In addition, EBNA3C stabilizes the E2F6 protein and is co-localized in the nucleus. We also demonstrated that both EBNA3C and E2F6 contribute to reduction in E2F1 transcriptional activity. Moreover, E2F1 forms a protein complex with EBNA3C and E2F6, and EBNA3C competes with E2F1 for E2F6 binding. E2F6 is also recruited by EBNA3C to the E2F1 promoter, which is critical for EBNA3C-mediated cell proliferation. These results demonstrate a critical role for E2F family members in EBV-induced malignancies, and provide new insights for targeting E2F transcription factors in EBV-associated cancers as potential therapeutic intervention strategies.

  1. EBV Nuclear Antigen 3C Mediates Regulation of E2F6 to Inhibit E2F1 Transcription and Promote Cell Proliferation

    PubMed Central

    Sun, Zhiguo; Jha, Hem Chandra; Saha, Abhik; Robertson, Erle S.

    2016-01-01

    Epstein–Barr virus (EBV) is considered a ubiquitous herpesvirus with the ability to cause latent infection in humans worldwide. EBV-association is evidently linked to different types of human malignancies, mainly of epithelial and lymphoid origin. Of interest is the EBV nuclear antigen 3C (EBNA3C) which is critical for EBV-mediated immortalization. Recently, EBNA3C was shown to bind the E2F1 transcription regulator. The E2F transcription factors have crucial roles in various cellular functions, including cell cycle, DNA replication, DNA repair, cell mitosis, and cell fate. Specifically, E2F6, one of the unique E2F family members, is known to be a pRb-independent transcription repressor of E2F-target genes. In our current study, we explore the role of EBNA3C in regulating E2F6 activities. We observed that EBNA3C plays an important role in inducing E2F6 expression in LCLs. Our study also shows that EBNA3C physically interacts with E2F6 at its amino and carboxy terminal domains and they form a protein complex in human cells. In addition, EBNA3C stabilizes the E2F6 protein and is co-localized in the nucleus. We also demonstrated that both EBNA3C and E2F6 contribute to reduction in E2F1 transcriptional activity. Moreover, E2F1 forms a protein complex with EBNA3C and E2F6, and EBNA3C competes with E2F1 for E2F6 binding. E2F6 is also recruited by EBNA3C to the E2F1 promoter, which is critical for EBNA3C-mediated cell proliferation. These results demonstrate a critical role for E2F family members in EBV-induced malignancies, and provide new insights for targeting E2F transcription factors in EBV-associated cancers as potential therapeutic intervention strategies. PMID:27548379

  2. Inflammation and Epstein-Barr Virus Infection Are Common Features of Myasthenia Gravis Thymus: Possible Roles in Pathogenesis

    PubMed Central

    Cavalcante, Paola; Maggi, Lorenzo; Colleoni, Lara; Caldara, Rosa; Motta, Teresio; Giardina, Carmelo; Antozzi, Carlo; Berrih-Aknin, Sonia; Bernasconi, Pia; Mantegazza, Renato

    2011-01-01

    The thymus plays a major role in myasthenia gravis (MG). Our recent finding of a persistent Epstein-Barr (EBV) virus infection in some MG thymuses, combined with data showing that the thymus is in a proinflammatory state in most patients, supports a viral contribution to the pathogenesis of MG. Aim of this study was to gain further evidence for intrathymic chronic inflammation and EBV infection in MG patients. Transcriptional profiling by low density array and real-time PCR showed overexpression of genes involved in inflammatory and immune response in MG thymuses. Real-time PCR for EBV genome, latent (EBER1, EBNA1, LMP1) and lytic (BZLF1) transcripts, and immunohistochemistry for LMP1 and BZLF1 proteins confirmed an active intrathymic EBV infection, further supporting the hypothesis that EBV might contribute to onset or perpetuation of the autoimmune response in MG. Altogether, our results support a role of inflammation and EBV infection as pathogenic features of MG thymus. PMID:21961056

  3. Multiple Epstein-Barr virus infections in healthy individuals

    NASA Technical Reports Server (NTRS)

    Walling, Dennis M.; Brown, Abigail L.; Etienne, Wiguins; Keitel, Wendy A.; Ling, Paul D.; Butel, J. S. (Principal Investigator)

    2003-01-01

    We employed a newly developed genotyping technique with direct representational detection of LMP-1 gene sequences to study the molecular epidemiology of Epstein-Barr virus (EBV) infection in healthy individuals. Infections with up to five different EBV genotypes were found in two of nine individuals studied. These results support the hypothesis that multiple EBV infections of healthy individuals are common. The implications for the development of an EBV vaccine are discussed.

  4. AIDS-Related EBV-Associated Smooth Muscle Tumors: A Review of 64 Published Cases

    PubMed Central

    Purgina, Bibianna; Rao, Uma N. M.; Miettinen, Markku; Pantanowitz, Liron

    2011-01-01

    The number of reported cases of smooth muscle tumor (SMT) arising in patients with AIDS has been increasing since the mid-1990s. The aim of this study is to characterize the epidemiology, clinical manifestations, pathologic features, prognosis and, management of Epstein-Barr virus-related SMT (EBV-SMT) in patients with AIDS. An English language literature search identified 53 articles including 64 reported cases of EBV-SMT. The majority of these reports involved patients who were young, severely immunosuppressed, and had multifocal tumors. The central nervous system was the most common site to be involved. Histologically, tumors had smooth muscle features and were immunoreactive for muscle markers and all but two tumors demonstrated the presence of EBV by either immunohistochemistry, in situ hybridization, and/or PCR. While mitoses and/or necrosis were used to separate leiomyoma from leiomyosarcoma, these features did not correlate with clinical outcome. Treatment included primarily resection, and less often radiotherapy, chemotherapy and highly active antiretroviral therapy (HAART). Overall, EBV-SMTs appear to have variable aggressiveness and clinical outcome and may exhibit a more favorable prognosis compared to conventional leiomyosarcoma. Tumor-related death from EBV-SMT occurred in only 4 of 51 patients. PMID:21437186

  5. Development of a competitive PCR method for physical titration of recombinant EBV vector in a helper-dependent packaging system.

    PubMed

    Wang, J; Vos, J M

    2001-06-01

    Epstein-Barr virus (EBV) is a gamma-herpesvirus with B lymphotropism and a double-stranded DNA genome of 172 kb that is episomally maintained in permissive cells during latency. EBV-based vectors containing minimal cis elements for replication, amplification, and helper-dependent packaging in a producer cell line HH514 have been developed to deliver therapeutic/suicide transgenes as infectious viral particles (miniEBV) to EBV-transformed B lymphoblastoid cells or B lymphoma cells. A quantitative, competitive PCR-based assay was developed to determine the relative packaging efficiencies of miniEBV and helper P3HR1 coproduced in HH514 cells. This provides a rapid and accurate quantitation of the physical titer of the virus preparation, which helps preserve the biological titer of the virus preparation and increase the efficiency of transgene delivery by miniEBV infection. In addition, it provides a sensitive and accurate way to evaluate future development of a helper-free packaging system by detecting any possible helper virus contamination.

  6. Chronic Physical Stress Does Not Interact with Epstein-Barr Virus (EBV)-Encoded Dutpase to Alter the Sickness Response

    PubMed Central

    Weil, Zachary M.; Abi Salloum, Bachir; Ariza, Maria Eugenia; Williams, Marshall; Reader, Brenda; Glaser, Ronald; Sheridan, John; Nelson, Randy J.

    2016-01-01

    Most adult humans have been infected with Epstein-Barr virus (EBV), which is thought to contribute to the development of chronic fatigue syndrome. Stress is known to influence the immune system and can exacerbate the sickness response. Although a role for psychological stress in the sickness response, particularly in combination with EBV-encoded deoxyuridine triphosphate nucleotidohydrolase (dUTPase) has been established, and the role of physical stressors in these interactions remains unspecified. In this study, we seek to determine the interaction of chronic physical (swim) stress and EBV-encoded dUTPase injection. We hypothesize that a chronic physical stressor will exacerbate the sickness response following EBV-encoded dUTPase injection. To test this hypothesis mice receive daily injections of EBV-encoded dUTPase or vehicle and are subjected to 15 min of swim stress each day for 14 days or left unmanipulated. On the final evening of injections mice undergo behavioral testing. EBV-encoded dUTPase injection alone produces some sickness behaviors. The physical swimming stress does not alter the sickness response. PMID:27175311

  7. Hypovitaminosis-D and EBV: no interdependence between two MS risk factors in a healthy young UK autumn cohort.

    PubMed

    Ramien, Caren; Pachnio, Annette; Sisay, Sofia; Begum, Jusnara; Leese, Alison; Disanto, Giulio; Kuhle, Jens; Giovannoni, Gavin; Rickinson, Alan; Ramagopalan, Sreeram V; Moss, Paul; Meier, Ute-Christiane

    2014-05-01

    Late Epstein-Barr virus infection and hypovitaminosis-D as environmental risk factors in the pathogenesis of multiple sclerosis are gaining great interest. We, therefore, tested for in-vivo interdependence between Epstein-Barr-virus (EBV)-status and 25-hydroxyvitamin D3 (25(OH)D3) -level in healthy young individuals from a United Kingdom (UK) autumn cohort. EBV-load was measured by quantitative polymerase chain reaction and 25(OH)D3 levels by isotope-dilution liquid chromatography-tandem mass spectrometry. This young, healthy UK autumn cohort showed surprisingly low levels of 25(OH)D3 (mean value: 40.5 nmol/L ± 5.02). Furthermore, we found that low 25(OH)D3 levels did not impact on EBV load and anti-EBV nuclear antigen-1 (EBNA-1) titers. However, we observed a correlation between EBV load and EBNA-1 titers. These observations should be of value in the study of the potential relationship between hypovitaminosis-D and EBV-status in the pathophysiology of multiple sclerosis. PMID:24192216

  8. HLA Allele E*01:01 Is Associated with a Reduced Risk of EBV-Related Classical Hodgkin Lymphoma Independently of HLA-A*01/*02

    PubMed Central

    Martín, Paloma; Krsnik, Isabel; Navarro, Belen; Provencio, Mariano; García, Juan F.; Bellas, Carmen; Vilches, Carlos; Gomez-Lozano, Natalia

    2015-01-01

    Background An inefficient immune response against Epstein-Barr virus (EBV) infection is related to the pathogenesis of a subgroup of classical Hodgkin lymphomas (cHL). Some EBV immune-evasion mechanisms target HLA presentation, including the non-classical HLA-E molecule. HLA-E can be recognized by T cells via the TCR, and it also regulates natural killer (NK) cell signaling through the inhibitory CD94/NKG2A receptor. Some evidences indicate that EBV-infected B-cells promote the proliferation of NK subsets bearing CD94/NKG2A, suggesting a relevant function of these cells in EBV control. Variations in CD94/NKG2A-HLA-E interactions could affect NK cell-mediated immunity and, consequently, play a role in EBV-driven transformation and lymphomagenesis. The two most common HLA-E alleles, E*01:01 and E*01:03, differ by a single amino acid change that modifies the molecule function. We hypothesized that the functional differences in these variants might participate in the pathogenicity of EBV. Aim We studied two series of cHL patients, both with EBV-positive and-negative cases, and a cohort of unrelated controls, to assess the impact of HLA-E variants on EBV-related cHL susceptibility. Results We found that the genotypes with at least one copy of E*01:01 (i.e., E*01:01 homozygous and heterozygous) were underrepresented among cHL patients from both series compared to controls (72.6% and 71.6% vs 83%, p = 0.001). After stratification by EBV status, we found low rates of E*01:01-carriers mainly among EBV-positive cases (67.6%). These reduced frequencies are seen independently of other factors such as age, gender, HLA-A*01 and HLA-A*02, HLA alleles positively and negatively associated with the disease (adjusted OR = 0.4, p = 0.001). Furthermore, alleles from both HLA loci exert a cumulative effect on EBV-associated cHL susceptibility. Conclusions These results indicate that E*01:01 is a novel protective genetic factor in EBV-associated cHL and support a role for HLA

  9. A Novel Persistence Associated EBV miRNA Expression Profile Is Disrupted in Neoplasia

    PubMed Central

    Qiu, Jin; Cosmopoulos, Katherine; Pegtel, Michiel; Hopmans, Erik; Murray, Paul; Middeldorp, Jaap; Shapiro, Michael; Thorley-Lawson, David A.

    2011-01-01

    We have performed the first extensive profiling of Epstein-Barr virus (EBV) miRNAs on in vivo derived normal and neoplastic infected tissues. We describe a unique pattern of viral miRNA expression by normal infected cells in vivo expressing restricted viral latency programs (germinal center: Latency II and memory B: Latency I/0). This includes the complete absence of 15 of the 34 miRNAs profiled. These consist of 12 BART miRNAs (including approximately half of Cluster 2) and 3 of the 4 BHRF1 miRNAs. All but 2 of these absent miRNAs become expressed during EBV driven growth (Latency III). Furthermore, EBV driven growth is accompanied by a 5–10 fold down regulation in the level of the BART miRNAs expressed in germinal center and memory B cells. Therefore, Latency III also expresses a unique pattern of viral miRNAs. We refer to the miRNAs that are specifically expressed in EBV driven growth as the Latency III associated miRNAs. In EBV associated tumors that employ Latency I or II (Burkitt's lymphoma, Hodgkin's disease, nasopharyngeal carcinoma and gastric carcinoma), the Latency III associated BART but not BHRF1 miRNAs are up regulated. Thus BART miRNA expression is deregulated in the EBV associated tumors. This is the first demonstration that Latency III specific genes (the Latency III associated BARTs) can be expressed in these tumors. The EBV associated tumors demonstrate very similar patterns of miRNA expression yet were readily distinguished when the expression data were analyzed either by heat-map/clustering or principal component analysis. Systematic analysis revealed that the information distinguishing the tumor types was redundant and distributed across all the miRNAs. This resembles “secret sharing” algorithms where information can be distributed among a large number of recipients in such a way that any combination of a small number of recipients is able to understand the message. Biologically, this may be a consequence of functional redundancy between

  10. Reduced Transplacental Transfer of a Subset of Epstein-Barr Virus-Specific Antibodies to Neonates of Mothers Infected with Plasmodium falciparum Malaria during Pregnancy.

    PubMed

    Ogolla, Sidney; Daud, Ibrahim I; Asito, Amolo S; Sumba, Odada P; Ouma, Collins; Vulule, John; Middeldorp, Jaap M; Dent, Arlene E; Mehta, Saurabh; Rochford, Rosemary

    2015-11-01

    Over 35% of children in a region of malaria endemicity are infected with Epstein-Barr virus (EBV) by 6 months of age. This susceptibility may be linked to impaired transplacental transfer of antibodies. In this study, we determined the effect of malaria exposure during pregnancy on the transfer of EBV-specific maternal antibodies in a region of western Kenya that experiences endemic malaria. Pregnant mothers were recruited and followed up until delivery to determine levels of neonatal malaria exposure. Levels of EBV lytic (viral capsid antigen [VCA], Z transcriptional activator [Zta], and early diffuse antigen complex [EAd]) and EBV latent (EBV nuclear antigen-1 (EBNA1]) and tetanus-specific IgG antibodies were measured in 70 paired maternal and cord blood samples using a Luminex-bead-based assay. A high proportion (63%) of the infants were exposed to malaria in utero. Levels of EBV- and tetanus-specific antibodies were similar in malaria-infected mothers and in mothers who had no detectable malaria infection. Malaria-exposed neonates had significantly lower levels of anti-EBNA1, anti-Zta, and anti-EAd antibodies than were seen in their mothers. In utero malaria exposure resulted in significant reductions in transplacental transfer of anti-VCA-p18 and anti-EBNA1 antibodies of 13% and 22%, respectively. Neonates received significantly low levels of anti-Zta and anti-EAd antibodies irrespective of malaria exposure levels. In multivariate analysis, in utero malaria exposure was associated with a significant reduction in the transfer of anti-VCA-p18 and anti-EBNA1 antibodies to the neonates (P = 0.0234 and P = 0.0017, respectively). Malaria during pregnancy results in differential levels of transfer of EBV-specific antibodies from the mother to the fetus. The impaired transplacental transfer of some antibodies may lead to the malaria-exposed neonates being susceptible to early EBV infection. PMID:26376931

  11. EBV, HSV, CMV and HPV in laryngeal and oropharyngeal carcinoma in Polish patients.

    PubMed

    Polz-Gruszka, Dorota; Stec, Agnieszka; Dworzański, Jakub; Polz-Dacewicz, Małgorzata

    2015-03-01

    The role of viruses in the etiology of oral cancer has been proposed in many studies. The aim of the present study was to analyze the prevalence of Epstein-Barr virus, Human Herpes virus type 1, Cytomegalovirus and Human Papilloma virus among patients with oral squamous cell carcinoma in a Polish population. We investigated fresh-frozen tumor tissue fragments obtained from 80 patients with OSCC using the polymerase chain reaction assay. HPV was detected in 32.5% (22.5% were HPV 16), more often in laryngeal (36%) than in oropharyngeal carcinoma (26.6%). EBV was identified in 57.5%, HHV-1 in 7.5%, and CMV in 10% of patients. Co-infection with one or more viruses was detected in 30% of cases and most frequently it was co-infection with EBV and HPV (15%). Further studies are necessary to determine the potential role of EBV and the possible importance of HHV-1 as an infection co-factor in oropharyngeal cancer.

  12. Epstein–Barr Virus (EBV) Related Acute Liver Failure: A Case Series from the US Acute Liver Failure Study Group

    PubMed Central

    Mellinger, Jessica L.; Rossaro, Lorenzo; Naugler, Willscott E.; Nadig, Satish N.; Appelman, Henry; Lee, William M.; Fontana, Robert J.

    2014-01-01

    Purpose Acute liver failure (ALF) is a rare clinical syndrome associated with a high case fatality rate. Asymptomatic primary infection with Epstein–Barr virus (EBV) is common in the general population while acute hepatitis and jaundice are much less common and ALF has been rarely reported. We reviewed the presenting features as well as clinical outcomes amongst consecutive adults with EBV-related ALF. Methods Amongst the 1,887 adult ALF patients enrolled into the US ALF Study Group from January 1998 to February 2012, there were four patients (0.21 %) with EBV-related ALF. Diagnostic criteria for acute EBV infection included compatible serologies and/or the detection of EBV-encoded RNA (EBER) in liver tissue. Results Median patient age was 30 years (range 18–44); 75 % were male, and only 25 % were immunosuppressed. The median presenting ALT was 504 IU/mL (range 156–4,920), median Alk P was 431 (range 136–1,009), and median bilirubin was 17 mg/dL (range 13–22.1). Liver biopsy findings ranged from cholestasis to submassive necrosis with EBER + staining in two of the three samples tested. Although all of the patients were treated with an antiviral agent, two died of ALF, one underwent liver transplantation (LT) and one survived with supportive care and is well at 5 years. A review of the literature identified four additional LT recipients with favorable long-term outcomes. Conclusion Primary EBV infection accounts for <1 % of consecutive adult ALF cases but is associated with a high case fatality rate. LT is associated with favorable short- and long-term outcomes. PMID:24464209

  13. Comparison of the prognostic impact of serum anti-EBV antibody and plasma EBV DNA assays in nasopharyngeal carcinoma

    SciTech Connect

    Twu, C.-W.; Wang, W.-Y.; Liang, W.-M.; Jan, J.-S.; Jiang, R.-S.; Chao, Jeffrey; Jin, Y.-T.; Lin, J.-C. . E-mail: jclin@vghtc.gov.tw

    2007-01-01

    Purpose: Nasopharyngeal carcinoma (NPC) has been proven as an Epstein-Barr virus (EBV)-associated cancer. Serum anti-EBV antibodies and plasma EBV DNA have been investigated as surrogate markers for NPC. A comparison of the prognostic impacts of both assays has never been reported. Methods and Materials: Paired serum and plasma samples from 114 previously untreated NPC patients were collected and subjected to an immunofluorescence assay for immunoglobulin (Ig)A and IgG antibodies against the viral capsid antigen (VCA) and a real-time quantitative polymerase chain reaction assay for EBV DNA measurement. The effects of both assays on patient prognosis were thoroughly investigated. Results: Relapsed patients had significantly higher pretreatment EBV DNA concentration than patients without relapse (p 0.0006). No associations of VCA-IgA (p = 0.9669) or VCA-IgG (p = 0.6125) were observed between patients with and without relapse. The 4-year overall survival (60.3% vs. 93.1%, p < 0.0001) and relapse-free survival rates (54.4% vs. 77.9%, p = 0.0009) were significantly lower in patients with higher pretreatment EBV DNA load than in those with lower EBV DNA load. Patients with persistently detectable EBV DNA after treatment had significantly worse 4-year overall (30.8% vs. 84.6%, p < 0.0001) and relapse-free survival rates (15.4% vs. 74.0%, p < 0.0001) than those with undetectable EBV DNA. The VCA-IgA and VCA-IgG titer could not predict survivals (all p > 0.1). Cox multivariate analyses also showed the same results. Conclusion: Plasma EBV DNA is superior to serum EBV VCA antibodies in prognostic predictions for NPC.

  14. Flow cytometric analysis of skin blister fluid induced by mosquito bites in a patient with chronic active Epstein-Barr virus infection.

    PubMed

    Wada, Taizo; Yokoyama, Tadafumi; Nakagawa, Hiroyasu; Asai, Erika; Toga, Akiko; Sakakibara, Yasuhisa; Shibata, Fumie; Tone, Yumi; Shimizu, Masaki; Toma, Tomoko; Yachie, Akihiro

    2009-12-01

    In chronic active Epstein-Barr virus (EBV) infection (CAEBV), ectopic EBV infection has been described in T or natural killer (NK) cells. NK cell-type infection (NK-CAEBV) is characterized by large granular lymphocytosis, high IgE levels and unusual reactions to mosquito bites, including severe local skin reactions, fever and liver dysfunction. However, the mechanisms underlying these reactions remain undetermined. Herein, we describe a patient with NK-CAEBV whose blister fluid after mosquito bites was analyzed. The patient exhibited significant increases in the percentage of CD56(+) NK cells in the fluid compared with a simple mosquito allergy, in which the majority of infiltrated cells were CD203c(+) cells, indicating basophils and/or mast cells. His fluid also contained CD203c(+) cells, and his circulating basophils were activated by mosquito extracts in vitro. These results suggest that CD203c(+) cells as well as NK cells may play pathogenic roles in the severe skin reactions to mosquito bites in NK-CAEBV.

  15. The expression of EBV-encoded LMP1 in young patients with lupus nephritis

    PubMed Central

    Ding, Yan; He, Xiaojie; Liao, Wang; Yi, Zhuwen; Yang, Huilan; Xiang, Wei

    2015-01-01

    One of the major disease manifestations of systemic lupus erythematosus (SLE) is lupus nephritis (LN), and the underlying mechanisms are not yet understood. Epstein-Barr virus (EBV) reactivation was associated with the induction of SLE, with EBV-encoded latent membrane protein1 (LMP1) plays a vital role in this process. Although it was reported that LN was associated with LMP1, most of these results are from patients with ages differed greatly (range, 10-56 years). Given the increased prevalence of EBV infection in young patients, we focused on the association of LN and LMP1 expression in the renal tissues of young patients (range, 6-16 years) in this study. We found that the positive rate of LMP1 in the renal tissues was significantly higher in patients with LN compared with control (P<0.001), which is consistent with the previous reports. The positive rates of LMP1 were similar between the patients of initial onset and relapse, and there was no detectable difference between the patients with and without concurrent infection (P>0.05). However, we reported for the first time about the positive correlation of LMP1 with classification of LN. The proportion of young patients positive for anti‑Sm antibody was significantly higher in the LMP1 positive group compared with the LMP1 negative control (P>0.05). These results indicate that EBV infection in the renal of young patients may lead to the increased severity of LN, and the expression of anti-Sm is likely contributed to this process. PMID:26131206

  16. Control of the Inflammatory Response Mechanisms Mediated by Natural and Induced Regulatory T-Cells in HCV-, HTLV-1-, and EBV-Associated Cancers

    PubMed Central

    Moralès, Olivier; Delhem, Nadira

    2014-01-01

    Virus infections are involved in chronic inflammation and, in some cases, cancer development. Although a viral infection activates the immune system's response that eradicates the pathogen mainly through inflammatory mechanisms, it is now recognized that this inflammatory condition is also favorable to the development of tumors. Indeed, it is well described that viruses, such as hepatitis C virus (HCV), Epstein Barr virus (EBV), human papillomavirus (HPV) or human T-cell lymphotropic virus type-1 (HTLV-1), are important risk factors for tumor malignancies. The inflammatory response is a fundamental immune mechanism which involves several molecular and cellular components consisting of cytokines and chemokines that are released by various proinflammatory cells. In parallel to this process, some endogenous recruited components release anti-inflammatory mediators to restore homeostasis. The development of tools and strategies using viruses to hijack the immune response is mostly linked to the presence of regulatory T-cells (Treg) that can inhibit inflammation and antiviral responses of other effector cells. In this review, we will focus on current understanding of the role of natural and induced Treg in the control and the resolution of inflammatory response in HCV-, HTLV-1-, and EBV-associated cancers. PMID:25525301

  17. Genome-wide analysis of Epstein-Barr virus (EBV) isolated from EBV-associated gastric carcinoma (EBVaGC)

    PubMed Central

    Yang, Wenjun; Pan, Yaqi; Ji, Jiafu; Ke, Yang

    2016-01-01

    Epstein-Barr virus (EBV) is linked to the development of a variety of malignancies, including EBV-associated gastric carcinoma (EBVaGC). In this study, EBVaGC was detected in 15 (7.3%) of 206 GC cases. To identify the EBV genomic variation, EBV genomic sequences isolated from 9 EBVaGC biopsy specimens were successfully retrieved, designated EBVaGC1 to EBVaGC9. By comparative analysis of these strains with another 6 completely sequenced EBV strains, EBV-wild type, B95–8, AG876, GD1, GD2, and HKNPC1, it was demonstrated that EBVaGC1 to 9 were most closely related to the GD1 strain. Phylogenetic analysis of the GC biopsy specimen-derived EBV (GC-EBV) genomes was subsequently performed to assess their genomic diversity and it exhibited the greatest divergence from the type 2 strain, AG876. Compared with the reference EBV strain GD1, they harbored 961 variations in total, including 919 substitutions, 23 insertions, and 19 deletions. Single nucleotide polymorphism (SNP) density varied substantially across all known open reading frames and was highest in latency-associated genes. Moreover, we identified 2 interstrain recombinants at the EBNA1 locus, which provided a further mechanism for the generation of diversity. Some T-cell epitope sequences in EBNA1 and LMP2A genes showed extensive variation across strains, which implied their importance in the development of vaccines and T-cell therapy. In conclusion, we reported the first genome-wide view of sequence variation of EBV isolated from primary EBVaGC biopsy specimens, which might serve as an effective method for further understanding the genomic variations contribute to EBVaGC carcinogenesis and treatment. PMID:26716899

  18. Increased EBV Shedding in Astronaut Saliva During Spaceflight

    NASA Technical Reports Server (NTRS)

    Pierson, D. L.; Stowe, R. P.; Phillips, T.; Lugg, D. J.; Mehta, S. K.

    2003-01-01

    Shedding of Epstein-Barr virus (EBV) by astronauts before, during, and after space shuttle missions was quantified. Of 1398 saliva specimens from 32 astronauts, 314 (23%) were positive for EBV DNA by PCR analysis. Of the saliva specimens collected before flight, 29% were positive for EBV DNA and of those collected during or after flight, 16% were EBV-positive. The number of EBV DNA copies from samples taken during the flight was 417+/-31, significantly higher (P < 0.05) than the number of copies from the preflight (40+/-1.7) and postflight (44+/-5) phases. Eighteen control subjects shed EBV DNA with a frequency of 3.7% and a copy number of 40+/-2 per ml saliva. Ten days before flight and on landing day, antibody titers to EBV viral capsid antigen (VCA) were significantly (P < 0.05) higher than baseline levels. On landing day, urinary level of cortiso1 and catecholamines, and plasma levels of substance P and other neuropeptides, were increased over their preflight value. Results suggested that stress associated with spaceflight decreases cellular immunity and thereby leads to increased viral reactivation.

  19. DNA Damage Signaling Is Induced in the Absence of Epstein-Barr Virus (EBV) Lytic DNA Replication and in Response to Expression of ZEBRA.

    PubMed

    Wang'ondu, Ruth; Teal, Stuart; Park, Richard; Heston, Lee; Delecluse, Henri; Miller, George

    2015-01-01

    Epstein Barr virus (EBV), like other oncogenic viruses, modulates the activity of cellular DNA damage responses (DDR) during its life cycle. Our aim was to characterize the role of early lytic proteins and viral lytic DNA replication in activation of DNA damage signaling during the EBV lytic cycle. Our data challenge the prevalent hypothesis that activation of DDR pathways during the EBV lytic cycle occurs solely in response to large amounts of exogenous double stranded DNA products generated during lytic viral DNA replication. In immunofluorescence or immunoblot assays, DDR activation markers, specifically phosphorylated ATM (pATM), H2AX (γH2AX), or 53BP1 (p53BP1), were induced in the presence or absence of viral DNA amplification or replication compartments during the EBV lytic cycle. In assays with an ATM inhibitor and DNA damaging reagents in Burkitt lymphoma cell lines, γH2AX induction was necessary for optimal expression of early EBV genes, but not sufficient for lytic reactivation. Studies in lytically reactivated EBV-positive cells in which early EBV proteins, BGLF4, BGLF5, or BALF2, were not expressed showed that these proteins were not necessary for DDR activation during the EBV lytic cycle. Expression of ZEBRA, a viral protein that is necessary for EBV entry into the lytic phase, induced pATM foci and γH2AX independent of other EBV gene products. ZEBRA mutants deficient in DNA binding, Z(R183E) and Z(S186E), did not induce foci of pATM. ZEBRA co-localized with HP1β, a heterochromatin associated protein involved in DNA damage signaling. We propose a model of DDR activation during the EBV lytic cycle in which ZEBRA induces ATM kinase phosphorylation, in a DNA binding dependent manner, to modulate gene expression. ATM and H2AX phosphorylation induced prior to EBV replication may be critical for creating a microenvironment of viral and cellular gene expression that enables lytic cycle progression. PMID:25950714

  20. DNA Damage Signaling Is Induced in the Absence of Epstein-Barr Virus (EBV) Lytic DNA Replication and in Response to Expression of ZEBRA.

    PubMed

    Wang'ondu, Ruth; Teal, Stuart; Park, Richard; Heston, Lee; Delecluse, Henri; Miller, George

    2015-01-01

    Epstein Barr virus (EBV), like other oncogenic viruses, modulates the activity of cellular DNA damage responses (DDR) during its life cycle. Our aim was to characterize the role of early lytic proteins and viral lytic DNA replication in activation of DNA damage signaling during the EBV lytic cycle. Our data challenge the prevalent hypothesis that activation of DDR pathways during the EBV lytic cycle occurs solely in response to large amounts of exogenous double stranded DNA products generated during lytic viral DNA replication. In immunofluorescence or immunoblot assays, DDR activation markers, specifically phosphorylated ATM (pATM), H2AX (γH2AX), or 53BP1 (p53BP1), were induced in the presence or absence of viral DNA amplification or replication compartments during the EBV lytic cycle. In assays with an ATM inhibitor and DNA damaging reagents in Burkitt lymphoma cell lines, γH2AX induction was necessary for optimal expression of early EBV genes, but not sufficient for lytic reactivation. Studies in lytically reactivated EBV-positive cells in which early EBV proteins, BGLF4, BGLF5, or BALF2, were not expressed showed that these proteins were not necessary for DDR activation during the EBV lytic cycle. Expression of ZEBRA, a viral protein that is necessary for EBV entry into the lytic phase, induced pATM foci and γH2AX independent of other EBV gene products. ZEBRA mutants deficient in DNA binding, Z(R183E) and Z(S186E), did not induce foci of pATM. ZEBRA co-localized with HP1β, a heterochromatin associated protein involved in DNA damage signaling. We propose a model of DDR activation during the EBV lytic cycle in which ZEBRA induces ATM kinase phosphorylation, in a DNA binding dependent manner, to modulate gene expression. ATM and H2AX phosphorylation induced prior to EBV replication may be critical for creating a microenvironment of viral and cellular gene expression that enables lytic cycle progression.

  1. Unusual Indolent Course of a Chronic Active Epstein-Barr Virus-Associated Natural Killer Cell Lymphoproliferative Disorder

    PubMed Central

    Al-Riyami, Arwa Z.; Al-Farsi, Khalil; Al-Khabori, Murtadha; Al-Huneini, Mohammed; Al-Hadabbi, Ibrahim

    2016-01-01

    Natural killer (NK) cell lymphoproliferative disorders are uncommon and the Epstein-Barr virus (EBV) plays an important aetiological role in their pathogenesis. We report a 20-year-old male with a chronic active EBV infection associated with a NK cell lymphoproliferative disorder which had an unusual indolent course. He presented to the Sultan Qaboos University Hospital in Muscat, Oman, in December 2011 with a history of intermittent fever and coughing. Examinations revealed generalised lymphadenopathy, hepatosplenomegaly, leukocytosis, transaminitis, diffuse bilateral lung infiltrates and bone marrow lymphocyte involvement. A polymerase chain reaction (PCR) test revealed a high EBV viral load in the peripheral blood cells. The patient received a course of piperacillin-tazobactam for Klebsiella pneumoniae, but no active treatment for the lymphoproliferative disorder. However, his lymphocyte count, serum lactate dehydrogenase and liver enzymes dropped spontaneously. In addition, EBV PCR copies fluctuated and then decreased significantly. He remained clinically asymptomatic over the following four years. PMID:27226916

  2. Virus-Specific CD8(+) T Cells Cross-Reactive to Donor-Alloantigen Are Transiently Present in the Circulation of Kidney Transplant Recipients Infected With CMV and/or EBV.

    PubMed

    Heutinck, K M; Yong, S L; Tonneijck, L; van den Heuvel, H; van der Weerd, N C; van der Pant, K A M I; Bemelman, F J; Claas, F H J; Ten Berge, I J M

    2016-05-01

    T cells play a dual role in transplantation: They mediate transplant rejection and are crucial for virus control. Memory T cells generated in response to pathogens can cross-react to alloantigen, a phenomenon called heterologous immunity. Virus-specific CD8(+) T cells cross-reacting to donor-alloantigen might affect alloimmune responses and hamper tolerance induction following transplantation. Here, we longitudinally studied these cross-reactive cells in peripheral blood of 25 kidney transplant recipients with a cytomegalovirus and/or Epstein-Barr virus infection. Cross-reactive T cells were identified by flow cytometry as virus-specific T cells that proliferate in response to donor cells in a mixed-lymphocyte reaction. In 13 of 25 patients, we found cross-reactivity to donor cells for at least 1 viral epitope before (n = 7) and/or after transplantation (n = 8). Cross-reactive T cells were transiently present in the circulation, and their precursor frequency did not increase following transplantation or viral infection. Cross-reactive T cells expressed interferon-γ and CD107a in response to both alloantigen and viral peptide and resembled virus-specific T cells in phenotype and function. Their presence was not associated with impaired renal function, proteinuria, or rejection. In conclusion, virus-specific T cells that cross-react to donor-alloantigen are transiently detectable in the circulation of kidney transplant recipients. PMID:26603974

  3. Middle ear squamous papilloma: A report of four cases analyzed by HPV and EBV in situ hybridization

    PubMed Central

    ZHOU, HAN; CHEN, ZHIBIN; ZHANG, WEIMING; XING, GUANGQIAN

    2014-01-01

    Squamous papilloma involving the middle ear as a primary lesion is an extremely rare occurrence. The aims of the present study were to investigate the presence of human papilloma virus (HPV) and Epstein-Barr virus (EBV) infections in primary middle ear squamous papilloma and to describe the clinical and pathological features of the disease along with therapeutic strategies. A retrospective review was conducted of four patients with clinical and pathological diagnoses of middle ear squamous papilloma. In situ hybridization (ISH) for a wide range of HPV DNA subtypes and EBV-encoded RNA was performed in the tissue samples obtained from these patients. Only two cases of primary squamous papilloma in the middle ear have been previously reported in the English literature. These papillomas developed in males of ~60-years of age and otorrhea was the most frequent complaint. Premalignant changes were observed in two of the present cases and ISH of HPV and EBV was negative in all four cases. The results of the present study indicated that chronic inflammatory stimulation, not HPV and EBV infection, is involved in the occurrence of middle ear squamous papilloma and its malignant transformation. Radical surgery and long-term postoperative follow-up are recommended due to its malignant and recurrent potential. Further genetic investigations with additional new cases are required to clarify the pathogenesis of squamous papilloma involving the middle ear. PMID:24348817

  4. Synergistic activation of cells by Epstein-Barr virus and B-cell growth factor.

    PubMed Central

    Hutt-Fletcher, L M

    1987-01-01

    Infection with Epstein-Barr virus (EBV) is initiated by virus binding to the C3dg-C3d receptor CR2. Several workers have implicated this receptor in the control of B-cell activation by examining the effects of antibodies to CR2 and isolated C3d on B-cell proliferation and differentiation. We report here on the activating effects of irradiated EBV, which retains its capacity to bind to CR2 but loses its ability to function as a T-independent B-cell activator. EBV synergized with B-cell growth factor in the induction of uptake of tritiated thymidine by T cell-depleted leukocytes from seronegative donors but did not induce secretion of immunoglobulin. Synergism could be inhibited with an anti-viral antibody that inhibited binding of EBV to CR2. No similar synergism was found between EBV and recombinant interleukin 2, interleukin 1 alpha, or gamma interferon or with the lipid A fraction of bacterial lipopolysaccharide. EBV may thus initiate B-cell activation as it binds to CR2. Infectious virus may, under normal circumstances, induce the cell to make those growth factors necessary to support B-cell proliferation; the difficulty of transforming cells with transfected EBV DNA may in part reflect the absence of an activation event provided by intact virus as it attaches to CR2. The synergism of EBV and B-cell growth factor more clearly distinguishes the effects of B-cell growth factor from those of interleukin 1 and interleukin 2 in other models of B-cell activation. Thus, this may be a useful model for further delineation of unique effects of B-cell growth factor on B-cell function. PMID:3027404

  5. Immunologic difference between hypersensitivity to mosquito bite and hemophagocytic lymphohistiocytosis associated with Epstein-Barr virus infection.

    PubMed

    Lee, Wen-I; Lin, Jainn-Jim; Hsieh, Meng-Ying; Lin, Syh-Jae; Jaing, Tang-Her; Chen, Shih-Hsiang; Hung, Iou-Jih; Yang, Chao-Ping; Chen, Chin-Jung; Huang, Yhu-Chering; Li, Shin-Pai; Huang, Jing-Long

    2013-01-01

    Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening, virus-triggered immune disease. Hypersensitivity to mosquito bite (HMB), a presentation of Chronic Active Epstein-Barr Virus infection (CAEBV), may progress to HLH. This study aimed to investigate the immunologic difference between the HMB episodes and the HLH episodes associated with EBV infection. Immunologic changes of immunoglobulins, lymphocyte subsets, cytotoxicity, intracellular perforin and granzyme expressions, EBV virus load and known candidate genes for hereditary HLH were evaluated and compared. In 12 HLH episodes (12 patients) and 14 HMB episodes (4 patients), there were both decreased percentages of CD4+ and CD8+ and increased memory CD4+ and activated (CD2+HLADR+) lymphocytes. In contrast to HMB episodes that had higher IgE levels and EBV virus load predominantly in NK cells, those HLH episodes with virus load predominantly in CD3+ lymphocyte had decreased perforin expression and cytotoxicity that were recovered in the convalescence period. However, there was neither significant difference of total virus load in these episodes nor candidate genetic mutations responsible for hereditary HLH. In conclusion, decreased perforin expression in the HLH episodes with predominant-CD3+ EBV virus load is distinct from those HMB episodes with predominant-NK EBV virus load. Whether the presence of non-elevated memory CD4+ cells or activated lymphocytes (CD2+HLADR+) increases the mortality rate in the HLH episodes remains to be further warranted through larger-scale studies.

  6. CD4+ and CD8+ T-Cell Responses to Latent Antigen EBNA-1 and Lytic Antigen BZLF-1 during Persistent Lymphocryptovirus Infection of Rhesus Macaques

    PubMed Central

    Leskowitz, R. M.; Zhou, X. Y.; Villinger, F.; Fogg, M. H.; Kaur, A.; Lieberman, P. M.; Wang, F.

    2013-01-01

    Epstein-Barr virus (EBV) infection leads to lifelong viral persistence through its latency in B cells. EBV-specific T cells control reactivations and prevent the development of EBV-associated malignancies in most healthy carriers, but infection can sometimes cause chronic disease and malignant transformation. Epstein-Barr nuclear antigen 1 (EBNA-1) is the only viral protein consistently expressed during all forms of latency and in all EBV-associated malignancies and is a promising target for a therapeutic vaccine. Here, we studied the EBNA-1-specific immune response using the EBV-homologous rhesus lymphocryptovirus (rhLCV) infection in rhesus macaques. We assessed the frequency, phenotype, and cytokine production profiles of rhLCV EBNA-1 (rhEBNA-1)-specific T cells in 15 rhesus macaques and compared them to the lytic antigen of rhLCV BZLF-1 (rhBZLF-1). We were able to detect rhEBNA-1-specific CD4+ and/or CD8+ T cells in 14 of the 15 animals screened. In comparison, all 15 animals had detectable rhBZLF-1 responses. Most peptide-specific CD4+ T cells exhibited a resting phenotype of central memory (TCM), while peptide-specific CD8+ T cells showed a more activated phenotype, belonging mainly to the effector cell subset. By comparing our results to the human EBV immune response, we demonstrate that the rhLCV model is a valid system for studying chronic EBV infection and for the preclinical development of therapeutic vaccines. PMID:23698300

  7. Measurement of CD8+ and CD4+ T Cell Frequencies Specific for EBV LMP1 and LMP2a Using mRNA-Transfected DCs.

    PubMed

    Sohn, Dae-Hee; Sohn, Hyun-Jung; Lee, Hyun-Joo; Lee, Seon-Duk; Kim, Sueon; Hyun, Seung-Joo; Cho, Hyun-Il; Cho, Seok-Goo; Lee, Suk-Kyeong; Kim, Tai-Gyu

    2015-01-01

    An EBV-specific cellular immune response is associated with the control of EBV-associated malignancies and lymphoproliferative diseases, some of which have been successfully treated by adoptive T cell therapy. Therefore, many methods have been used to measure EBV-specific cellular immune responses. Previous studies have mainly used autologous EBV-transformed B-lymphoblastoid cell lines (B-LCLs), recombinant viral vectors transfected or peptide pulsed dendritic cells (DCs) as stimulators of CD8(+) and CD4(+) T lymphocytes. In the present study, we used an interferon-γ (IFN-γ) enzyme-linked immunospot (ELISPOT) assay by using isolated CD8(+) and CD4(+) T cells stimulated with mRNA-transfected DCs. The frequency of latent membrane protein 1 (LMP1)-specific IFN-γ producing CD4(+) T cells was significantly higher than that of LMP2a. The frequency of IFN-γ producing CD4(+) T cells was significantly correlated with that of CD8(+) T cells in LMP1-specific immune responses (r = 0.7187, Pc < 0.0001). To determine whether there were changes in LMP1- or LMP2a-specific immune responses, subsequent peripheral blood mononuclear cells (PBMCs) samples were analyzed. Significant changes were observed in 5 of the 10 donors examined, and CD4(+) T cell responses showed more significant changes than CD8(+) T cell responses. CD8(+) and CD4(+) T cells from EBV-seropositive donors secreted only the Th1 cytokines IFN-γ, TNF-α, and IL-2, while Th2 (IL-4) and Th17 (IL-17a) cytokines were not detected. CD4(+) T cells secreted significantly higher cytokine levels than did CD8(+) T cells. Analysis of EBV-specific T cell responses using autologous DCs transfected with mRNA might provide a comprehensive tool for monitoring EBV infection and new insights into the pathogenesis of EBV-associated diseases. PMID:26023769

  8. Constitutive Interferon-Inducible Protein 16-Inflammasome Activation during Epstein-Barr Virus Latency I, II, and III in B and Epithelial Cells

    PubMed Central

    Ansari, Mairaj Ahmed; Singh, Vivek Vikram; Dutta, Sujoy; Veettil, Mohanan Valiya; Dutta, Dipanjan; Chikoti, Leela; Lu, Jie; Everly, David

    2013-01-01

    Epstein-Barr virus (EBV), etiologically linked with human B-cell malignancies and nasopharyngeal carcinoma (NPC), establishes three types of latency that facilitate its episomal genome persistence and evasion of host immune responses. The innate inflammasome responses recognize the pathogen-associated molecular patterns which lead into the association of a cytoplasmic sensor such as NLRP3 and AIM2 proteins or nuclear interferon-inducible protein 16 (IFI16) with adaptor ASC protein (apoptosis-associated speck-like protein with a caspase recruitment domain) and effector procaspase-1, resulting in active caspase-1 formation which cleaves the proforms of inflammatory interleukin-1β (IL-1β), IL-18, and IL-33 cytokines. Whether inflammasome responses recognize and respond to EBV genome in the nuclei was not known. We observed evidence of inflammasome activation, such as the activation of caspase-1 and cleavage of pro-IL-1β, -IL-18, and -IL-33, in EBV latency I Raji cells, latency II NPC C666-1 cells, and latency III lymphoblastoid cell lines (LCL). Interaction between ASC with IFI16 but not with AIM2 or NLRP3 was detected in all three latencies and during EBV infection of primary human B cells. IFI16 and cleaved caspase-1, IL-1β, IL-18, and IL-33 were detected in the exosomes from Raji cells and LCL. Though EBV nuclear antigen 1 (EBNA1) and EBV-encoded small RNAs (EBERs) are common to all forms of EBV latency, caspase-1 cleavage was not detected in cells expressing EBNA1 alone, and blocking EBER transcription did not inhibit caspase-1 cleavage. In fluorescence in situ hybridization (FISH) analysis, IFI16 colocalized with the EBV genome in LCL and Raji cell nuclei. These studies demonstrated that constant sensing of latent EBV genome by IFI16 in all types of latency results in the constitutive induction of the inflammasome and IL-1β, IL-18, and IL-33 maturation. PMID:23720728

  9. Human Papillomavirus Infections in Nonsexually Active Perinatally HIV Infected Children

    PubMed Central

    Puga, Ana; Farhat, Sepideh; Ma, Yifei

    2014-01-01

    Abstract Although human papillomavirus (HPV) infections are common in HIV-infected adults, little is known about children. Our objective was to examine the prevalence of and risks for HPV of the oral mucosal and external genital areas in nonsexually active (NSA) perinatally (P) HIV+ children and compare with HIV-exposed but uninfected (HEU) children. A convenience sample attending a pediatric clinic were enrolled. Samples for HPV were obtained from the oral and anogenital areas and tested for one of 37 HPV types. The mean age of the 48 PHIV+ children was 14.3±3.9 years vs. 6.2±4.8 for the 52 HEU (p<0.001). Of the 23 PHIV+ girls, 30.4% had anogenital and 17% had oral HPV, and of the 27 HEU girls, 2 (7.4%) anogenital and 0 had oral HPV. Of the boys, 4/23 (17.4%) and 1/25 (4%) PHIV+ had anogenital and oral HPV, respectively, and 3/24 (12.5%) and 1/25 (4%) HEU had anogenital and oral HPV, respectively. Rates of HPV did not differ by age among the PHIV+, whereas older HEU were more likely to have HPV than younger HEU (p=0.07). This large age gap precluded statistical comparison by HIV status. The presence of HPV in NSA PHIV+ children may have implications regarding HPV vaccination efficacy. PMID:24460009

  10. Evaluation of EBV transformation of human memory B-cells isolated by FACS and MACS techniques.

    PubMed

    Sadreddini, Sanam; Jadidi-Niaragh, Farhad; Younesi, Vahid; Pourlak, Tala; Afkham, Amir; Shokri, Fazel; Yousefi, Mehdi

    2016-07-01

    Several studies have been performed to develop effective neutralizing monoclonal antibodies. The Epstein-Barr virus (EBV) can efficiently immortalize B-cells to establish lymphoblastoid cell lines (LCL) and so it has been used extensively for transformation of B-cells to produce and secrete immunoglobulin. The present study addressed the effect of TLR7/8 agonist (R848), feeder cells layer and fluorescence-activated cell sorting (FACS) and magnetic-activated cell sorting (MACS) cell separation methods on the transformation efficiency of antibody-producing memory B-cells. For these studies, the antigen used for analyses of antibody formation was the tetanus neurotoxin (TeNT) derived from Clostridium tetani. The results here showed that employing an HFFF.PI6 feeder cell layer, R848 agonist and FACS-mediated purification of memory B-cells led to increased transformation efficiency. Altogether, the effects of the R848 and the feeder cells provided an efficient method for EBV transformation of human B-cells. Moreover, there was an advantage in using FACS sorting of B-cells over the MACS method in the context of EBV transformation and immortalization of precursors of antigen-specific B-cells.

  11. Evaluation of EBV transformation of human memory B-cells isolated by FACS and MACS techniques.

    PubMed

    Sadreddini, Sanam; Jadidi-Niaragh, Farhad; Younesi, Vahid; Pourlak, Tala; Afkham, Amir; Shokri, Fazel; Yousefi, Mehdi

    2016-07-01

    Several studies have been performed to develop effective neutralizing monoclonal antibodies. The Epstein-Barr virus (EBV) can efficiently immortalize B-cells to establish lymphoblastoid cell lines (LCL) and so it has been used extensively for transformation of B-cells to produce and secrete immunoglobulin. The present study addressed the effect of TLR7/8 agonist (R848), feeder cells layer and fluorescence-activated cell sorting (FACS) and magnetic-activated cell sorting (MACS) cell separation methods on the transformation efficiency of antibody-producing memory B-cells. For these studies, the antigen used for analyses of antibody formation was the tetanus neurotoxin (TeNT) derived from Clostridium tetani. The results here showed that employing an HFFF.PI6 feeder cell layer, R848 agonist and FACS-mediated purification of memory B-cells led to increased transformation efficiency. Altogether, the effects of the R848 and the feeder cells provided an efficient method for EBV transformation of human B-cells. Moreover, there was an advantage in using FACS sorting of B-cells over the MACS method in the context of EBV transformation and immortalization of precursors of antigen-specific B-cells. PMID:27043044

  12. Epstein-Barr virus infection induces bone resorption in apical periodontitis via increased production of reactive oxygen species.

    PubMed

    Jakovljevic, Aleksandar; Andric, Miroslav; Miletic, Maja; Beljic-Ivanovic, Katarina; Knezevic, Aleksandra; Mojsilovic, Slavko; Milasin, Jelena

    2016-09-01

    Chronic inflammatory processes in periapical tissues caused by etiological agents of endodontic origin lead to apical periodontitis. Apart from bacteria, two herpesviruses, Epstein-Barr virus (EBV) and Human cytomegalovirus (HCMV) are recognized as putative pathogens in apical periodontitis. Although previous reports suggest the involvement of EBV in the pathogenesis of apical periodontitis, its exact role in periapical bone resorption has not yet been fully elucidated. We hypothesize that EBV infection in apical periodontitis is capable of inducing periapical bone resorption via stimulation of reactive oxygen species (ROS) overproduction. Increased levels of ROS induce expression of receptor activator of nuclear factor kappa B (NF-κB) ligand (RANKL). RANKL binding to receptor activator of nuclear factor κB (RANK) present on the surface of preosteoclasts induces their maturation and activation which consequently leads to bone resorption. The potential benefit of antiviral and antioxidant-based therapies in periapical bone resorption treatment remains to be assessed. PMID:27515196

  13. Towards gene therapy for EBV-associated posttransplant lymphoma with genetically modified EBV-specific cytotoxic T cells.

    PubMed

    Ricciardelli, Ida; Blundell, Michael Patrick; Brewin, Jennifer; Thrasher, Adrian; Pule, Martin; Amrolia, Persis J

    2014-10-16

    Epstein-Barr virus (EBV)-associated posttransplant lymphoma (PTLD) is a major cause of morbidity/mortality after hematopoietic stem cell (SCT) or solid organ (SOT) transplant. Adoptive immunotherapy with EBV-specific cytotoxic lymphocytes (CTLs), although effective in SCT, is less successful after SOT where lifelong immunosuppression therapy is necessary. We have genetically engineered EBV-CTLs to render them resistant to calcineurin (CN) inhibitor FK506 through retroviral transfer of a calcineurin A mutant (CNA12). Here we examined whether or not FK506-resistant EBV-CTLs control EBV-driven tumor progression in the presence of immunosuppression in a xenogeneic mouse model. NOD/SCID/IL2rγ(null) mice bearing human B-cell lymphoma were injected with autologous CTLs transduced with either CNA12 or eGFP in the presence/absence of FK506. Adoptive transfer of autologous CNA12-CTLs induced dramatic lymphoma regression despite the presence of FK506, whereas eGFP-CTLs did not. CNA12-CTLs persisted longer, homed to the tumor, and expanded more than eGFP-CTLs in mice treated with FK506. Mice receiving CNA12-CTLs and treated with FK506 survived significantly longer than control-treated animals. Our results demonstrate that CNA12-CTL induce regression of EBV-associated tumors in vivo despite ongoing immunosuppression. Clinical application of this novel approach may enhance the efficacy of adoptive transfer of EBV-CTL in SOT patients developing PTLD without the need for reduction in immunosuppressive therapy.

  14. Mannose-Binding Lectin Genotypes and Susceptibility to Epstein-Barr Virus Infection in Infancy▿

    PubMed Central

    Friborg, Jeppe T.; Jarrett, Ruth F.; Koch, Anders; Garred, Peter; Freeland, June M. L.; Andersen, Andreas; Melbye, Mads

    2010-01-01

    In a cohort study of children <4 years of age in Greenland, mannose-binding lectin (MBL2) genotypes and Epstein-Barr virus (EBV) antibody levels were determined. EBV seropositivity was significantly lower and time to seroconversion increased in MBL-insufficient compared with MBL-sufficient children, indicating that MBL may be involved in primary EBV infection in infancy. PMID:20610664

  15. EBV latent membrane proteins (LMPs) 1 and 2 as immunotherapeutic targets: LMP-specific CD4+ cytotoxic T cell recognition of EBV-transformed B cell lines.

    PubMed

    Haigh, Tracey A; Lin, Xiaorong; Jia, Hui; Hui, Edwin P; Chan, Anthony T C; Rickinson, Alan B; Taylor, Graham S

    2008-02-01

    The EBV-latent membrane proteins (LMPs) 1 and 2 are among only three viral proteins expressed in EBV-associated Hodgkin's lymphoma and nasopharyngeal carcinoma. Since these tumors are HLA class I and class II-positive, the LMPs could serve as both CD8+ and CD4+ T cell targets. In contrast to CD8 responses, very little is known about CD4 responses to LMPs. In this study, we describe CD4+ T cell clones defining four LMP1- and three LMP2-derived peptide epitopes and their restricting alleles. All clones produced Th1-like cytokines in response to peptide and most killed peptide-loaded target cells by perforin-mediated lysis. Although clones to different epitopes showed different functional avidities in peptide titration assays, avidity per se was a poor predictor of the ability to recognize naturally infected B lymphoblastoid cell lines (LCLs) expressing LMPs at physiologic levels. Some epitopes, particularly within LMP1, consistently mediated strong LCL recognition detectable in cytokine release, cytotoxicity, and outgrowth inhibition assays. Using cyclosporin A to selectively block cytokine release, we found that CD4+ T cell cytotoxicity is the key effector of LCL outgrowth control. We therefore infer that cytotoxic CD4+ T cells to a subset of LMP epitopes could have therapeutic potential against LMP-expressing tumors.

  16. Virus-encoded microRNA contributes to the molecular profile of EBV-positive Burkitt lymphomas

    PubMed Central

    Piccaluga, Pier Paolo; Navari, Mohsen; De Falco, Giulia; Ambrosio, Maria Raffaella; Lazzi, Stefano; Fuligni, Fabio; Bellan, Cristiana; Rossi, Maura; Sapienza, Maria Rosaria; Laginestra, Maria Antonella; Etebari, Maryam; Rogena, Emily A.; Tumwine, Lynnette; Tripodo, Claudio; Gibellini, Davide; Consiglio, Jessica; Croce, Carlo M.; Pileri, Stefano A.; Leoncini, Lorenzo

    2016-01-01

    Burkitt lymphoma (BL) is an aggressive neoplasm characterized by consistent morphology and phenotype, typical clinical behavior and distinctive molecular profile. The latter is mostly driven by the MYC over-expression associated with the characteristic translocation (8;14) (q24; q32) or with variant lesions. Additional genetic events can contribute to Burkitt Lymphoma pathobiology and retain clinical significance. A pathogenetic role for Epstein-Barr virus infection in Burkitt lymphomagenesis has been suggested; however, the exact function of the virus is largely unknown. In this study, we investigated the molecular profiles (genes and microRNAs) of Epstein-Barr virus-positive and -negative BL, to identify specific patterns relying on the differential expression and role of Epstein-Barr virus-encoded microRNAs. First, we found significant differences in the expression of viral microRNAs and in selected target genes. Among others, we identified LIN28B, CGNL1, GCET2, MRAS, PLCD4, SEL1L, SXX1, and the tyrosine kinases encoding STK10/STK33, all provided with potential pathogenetic significance. GCET2, also validated by immunohistochemistry, appeared to be a useful marker for distinguishing EBV-positive and EBV-negative cases. Further, we provided solid evidences that the EBV-encoded microRNAs (e.g. BART6) significantly mold the transcriptional landscape of Burkitt Lymphoma clones. In conclusion, our data indicated significant differences in the transcriptional profiles of EBV-positive and EBV-negative BL and highlight the role of virus encoded miRNA. PMID:26325594

  17. B-lymphocyte subpopulations are equally susceptible to Epstein-Barr virus infection, irrespective of immunoglobulin isotype expression.

    PubMed

    Ehlin-Henriksson, Barbro; Gordon, John; Klein, George

    2003-04-01

    While Epstein-Barr virus (EBV) is known to establish latency in the memory B-cell compartment, there is controversy as to whether the memory or the naïve B cell is the initial target for infection. Here we have explored the infectability of the B-cell subsets contained in peripheral blood and tonsils, as distinguished by their surface expression of the immunoglobulin isotypes that help to define naïve and memory pools. First we show that both CD21 and major histocompatibility complex (MHC) class II molecules--respectively, the major receptor and co-receptor for EBV on B cells--are expressed at similar levels on blood and tonsillar B cells, irrespective of surface immunoglobulin class, indicating that each of the subsets demonstrate an equal potential, at least for infection. Then, following in vitro infection of total tonsillar B cells, we found that the relative frequencies of immunoglobulin (Ig)M-, IgG- and IgA-positive cells containing EBV-encoded Epstein-Barr virus nuclear antigen 5 (EBNA5) protein at 48 hr were similar to those of the starting population. However, IgD expression was uniformly decreased, probably as a consequence of cellular activation. These data indicate that recirculating B cells have both the potential for, and susceptibility to, initial infection by EBV, irrespective of the immunoglobulin isotype expressed.

  18. Trypsin activation pathway of rotavirus infectivity.

    PubMed Central

    Arias, C F; Romero, P; Alvarez, V; López, S

    1996-01-01

    The infectivity of rotaviruses is increased by and most probably is dependent on trypsin treatment of the virus. This proteolytic treatment specifically cleaves VP4, the protein that forms the spikes on the surface of the virions, to polypeptides VP5 and VP8. This cleavage has been reported to occur in rotavirus SA114fM at two conserved, closely spaced arginine residues located at VP4 amino acids 241 and 247. In this work, we have characterized the VP4 cleavage products of rotavirus SA114S generated by in vitro treatment of the virus with increasing concentrations of trypsin and with proteases AspN and alpha-chymotrypsin. The VP8 and VP5 polypeptides were analyzed by gel electrophoresis and by Western blotting (immunoblotting) with antibodies raised to synthetic peptides that mimic the terminal regions of VP4 generated by the trypsin cleavage. It was shown that in addition to arginine residues 241 and 247, VP4 is cleaved at arginine residue 231. These three sites were found to have different susceptibilities to trypsin, Arg-241 > Arg-231 > Arg-247, with the enhancement of infectivity correlating with cleavage at Arg-247 rather than at Arg-231 or Arg-241. Proteases AspN and alpha-chymotrypsin cleaved VP4 at Asp-242 and Tyr-246, respectively, with no significant enhancement of infectivity, although this enhancement could be achieved by further treatment of the virus with trypsin. The VP4 end products of trypsin treatment were a homogeneous VP8 polypeptide comprising VP4 amino acids 1 to 231 and a heterogeneous VP5, which is formed by two polypeptide species (present at a ratio of approximately 1:5) as a result of cleavage at either Arg-241 or Arg-247. A pathway for the trypsin activation of rotavirus infectivity is proposed. PMID:8709201

  19. [Epstein-Barr virus infection - life cycle, methods of diagnosis, associated diseases].

    PubMed

    Bocian, Joanna; Januszkiewicz-Lewandowska, Danuta

    2011-01-01

    Epstein-Barr virus (EBV) is a ubiquitous virus that infects about 90–95% of the adult population. EBV establishes life-long latent persistence. The virus is found to be the major cause of infectious mononucleosis but it has also been associated with development of endemic Burkitt’s lymphoma. Result of EBV infection is the most common complication in patients after transplantation which is a post-transplant lymphoproliferative disease. Strong associations between EBV infection and Hodgkin’s lymphoma, nasopharyngeal carcinoma, gastric carcinoma and carcinomas derived from smooth muscle tissue also exist. There is a hypothesis that there is an association between EBV infection and autoimmune and allergic diseases. EBV is a Herpesvirus family member; its genetic material has dsDNA form. There are two strains of EBV: A and B. The only host for EBV is human with target cells: B cells and epithelial cells. The life cycle of EBV consists of lytic and latent phases. In the latent phase three different patterns of gene expression are possible. Due to some circumstances EBV can undergo reactivation, which is an important issue in transplantology. The main methods of diagnosis of EBV infections are serological methods that detect certain specific antibodies and recently more popular molecular biological methods such as PCR or in situ hybridization. PMID:21677354

  20. Prevalence of Polyoma BK Virus (BKPyV), Epstein-Barr Virus (EBV) and Human Papilloma Virus (HPV) in Oropharyngeal Cancer.

    PubMed

    Polz-Gruszka, Dorota; Morshed, Kamal; Jarzyński, Adrian; Polz-Dacewicz, Małgorzata

    2015-01-01

    The aim of this study was to analyze the prevalence of BK virus, Human Papillomavirus and Epstein-Barr virus in oropharyngeal cancer, and to test our hypothesis that BKV/HPV/EBV co-infection plays a role in oropharyngeal squamous cell carcinoma. The correlation between viral infection, OSCC, anatomic location, pre-treatment staging, evidence of metastases to lymph nodes, and grading was also investigated. The examination samples were collected from 62 patients from paraffin tissue blocks. Males (90.3%) with, smoking (83.9%) and alcohol abuse (67.7%) problems prevailed in the studied group. G2 histological type was recognized in 80.6% cases. T4 (77.4%) and N2 (56.5%) traits occurred in the majority of patients. No cases of metastasis were observed (M0 100%). HPV - 24.2%, EBV - 27.4% and BKV 17.7% were detected in the studied samples. We observed co-infection EBV/BKV in 8% of cases, HPV/BKV in 4.8%, and HPV/EBV in 9% cases. Only in two cases co-infection of all three viruses was found.

  1. EBV-Induced Human CD8+ NKT Cells Synergise CD4+ NKT Cells Suppressing EBV-Associated Tumours Upon Induction of Th1-Bias

    PubMed Central

    Xiao, Wei; Li, Li; Zhou, Rui; Xiao, Ruijing; Wang, Yujuan; Ji, Xiang; Wu, Mengjun; Wang, Lan; Huang, Wei; Zheng, Xiaoling; Tan, Xinti; Chen, Lang; Xiong, Tao; Xiong, Jie; Jin, Youxin; Tan, Jinquan; He, Yuling

    2009-01-01

    CD8+ natural killer T (NKT) cells from EBV-associated tumour patients are quantitatively and functionally impaired. EBV-induced CD8+ NKT cells drive syngeneic T cells into a Th1-bias response to suppress EBV-associated malignancies. IL-4-biased CD4+ NKT cells do not affect either syngeneic T cell cytotoxicity or Th cytokine secretion. Circulating mDC1 cells from patients with EBV-associated malignancies impair the production of IFN-γ by CD8+ NKT cells. In this study, we have established a human-thymus-SCID chimaera model to further investigate the underlying mechanism of EBV-induced CD8+ NKT cells in suppressing EBV-associated malignancies. In the human-thymus-SCID chimera, EBV-induced CD8+ NKT cells suppress EBV-associated malignancies in a manner dependent on the Th1-bias response and syngeneic CD3+ T cells. However, adoptive transfer with CD4+ NKT cells alone inhibits T cell immunity. Interestingly, CD4+ NKT cells themselves secrete high levels of IL-2, enhancing the persistence of adoptively transferred CD8+ NKT cells and T cells, thereby leading to a more pronounced T cell anti-tumour response in chimaeras co-transferred with CD4+ CD8+ NKT cells. Thus, immune reconstitution with EBV-induced CD4+ and CD8+ NKT cells synergistically enhances T cell tumour immunity, providing a potential prophylactic and therapeutic treatment for EBV-associated malignancies. PMID:19887050

  2. Clinicopathologic and molecular features of 122 Brazilian cases of nodal and extranodal NK/T-cell lymphoma, nasal type, with EBV subtyping analysis.

    PubMed

    Gualco, Gabriela; Domeny-Duarte, Pollyanna; Chioato, Lucimara; Barber, Glen; Natkunam, Yasodha; Bacchi, Carlos E

    2011-08-01

    Extranodal natural killer/T-cell lymphoma, nasal type (NK/TCL) is more prevalent in Asia and in some areas of South and Central America, but it is rarely seen in the United States and Europe. In this study, a series of 122 cases of NK/TCL from Brazil was analyzed with respect to clinicopathologic features. Clinical characteristics and geographic distribution were evaluated in 97 cases of nasal/nasopharyngeal region and 23 cases in extranasal sites including 6 nodal cases. Clinical staging and follow-up information was available in a subset of 21 patients. All cases harbored Epstein-Barr virus (EBV), 95% and 85% expressed cytoplasmic CD3 and CD56, respectively, and all cases were positive for at least 1 marker for cytotoxic granules. The global distribution of EBV subtypes showed predominance of strain subtype A, 89%, and subtype B, 11%. No dual infections were detected. TCR-γ TCR-gene rearrangement was observed in 7 cases; all of them extranodal. Three of TCR-γ(+) cases showed EBV subtype A. Two TCR-γ(+)/CD56(+) cases showed EBV subtype B. Geographic distribution of NK/TCL showed higher frequency in the southeast and northeast regions of Brazil. Striking differences among geographic regions were seen with the vast majority of EBV subtype B (86%) occurring in the south and southeast regions.

  3. Functional analysis of the CD4(+) T-cell response to Epstein-Barr virus: T-cell-mediated activation of resting B cells and induction of viral BZLF1 expression.

    PubMed

    Fu, Z; Cannon, M J

    2000-07-01

    In contrast to the major role played by Epstein-Barr virus (EBV)-specific CD8(+) cytotoxic T-cell responses in immunosurveillance, recent studies have offered the apparently paradoxical suggestion that development of EBV-driven human B-cell lymphoproliferative disorders and tumors in SCID/hu mice is dependent on the presence of T cells, in particular CD4(+) T cells. This study presents a functional analysis of the CD4(+) T-cell response to EBV and shows that while CD4(+) T cells may be cytotoxic, they also express Th2 cytokines and CD40 ligand (gp39) and possess B-cell helper function. We show that EBV-specific CD4(+) T cells can provide non-HLA-restricted help for activation of resting B cells via a gp39-CD40-dependent pathway and are able to induce expression of BZLF1, a viral lytic cycle transactivator in latently infected resting B cells, ultimately resulting in rapid outgrowth of transformed B-cell colonies. These results support the proposal that CD4(+) T cells may play a key role in reactivation of latent EBV infection and may thus contribute to the pathogenesis of EBV-driven lymphoproliferative disorders.

  4. EBV-positive mucocutaneous ulcer in organ transplant recipients: a localized indolent posttransplant lymphoproliferative disorder.

    PubMed

    Hart, Melissa; Thakral, Beenu; Yohe, Sophia; Balfour, Henry H; Singh, Charanjeet; Spears, Michael; McKenna, Robert W

    2014-11-01

    Epstein-Barr virus (EBV)-positive mucocutaneous ulcer (EBV MCU) is a B-cell lymphoproliferative disorder occurring in elderly or iatrogenic immunocompromised patients. It has not been reported in solid organ transplant recipients. We observed 7 patients with EBV MCU in a cohort of 70 transplant recipients with EBV posttransplant lymphoproliferative disorder (PTLD). Transplants included: 5 renal, 1 heart, and 1 lung. Median patient age was 61; 5 were male. EBV MCU was observed in oral mucosa in 4 and gastrointestinal tract in 3. Duration of immunosuppressive therapy before EBV MCU was 0.6 to 13 years. Ulcers were undermined by inflammatory cells and polymorphic or monomorphic large cell lymphoproliferation. Reed-Sternberg-like cells were present in 5/7. Large B cells were CD20, CD30, and EBV-encoded RNA positive in all cases. Diagnosis in 3 recent patients was EBV MCU; 4 patients diagnosed before familiarity with EBV MCU were classified as monomorphic large cell (n=3) and polymorphic (n=1) PTLD. None of the patients had EBV DNA in their blood (<1000 copies/mL) at diagnosis or follow-up versus 35/44 transplant patients with systemic PTLD (P<0.001). All lesions resolved with reduced immunosuppression (7/7), change in immunosuppression (2/7), and rituximab (3/7). Five patients are living: 4 healthy, 1 awaiting second renal transplant. Two patients died 3 and 5 years after resolution of EBV MCU. No patient recurred with EBV MCU or other PTLDs. EBV MCU mimics more aggressive categories of PTLD but lacks EBV DNA in blood, which may be a useful distinguishing feature. Lesions are likely to resolve with conservative management. Awareness of EBV MCU in the posttransplant setting is necessary for appropriate diagnosis and treatment.

  5. Natural killer T cell strategies to combat Epstein–Barr virus infection

    PubMed Central

    Priatel, John J; Chung, Brian K; Tsai, Kevin; Tan, Rusung

    2014-01-01

    Epstein–Barr virus (EBV) infection results in rapid loss of CD1d expression from the surface of infected B cells, thus enabling the virus to evade immune recognition by natural killer T (NKT) cells. Using pharmacologic means to boost CD1d expression, potent NKT cell effector functions can be elicited toward EBV-infected B cells, suggesting the promise of novel strategies to target EBV-associated diseases such as some B-cell malignancies. PMID:25050206

  6. Incidence and Risk of Infection in Egyptian Patients with Systemic Lupus Erythematosus

    PubMed Central

    Mohamed, Dalia F; Habeeb, Reem A; Hosny, Sherin M; Ebrahim, Shafika E

    2014-01-01

    BACKGROUND Infection in systemic lupus erythematosus (SLE) is common and is one of the leading causes of morbidity and mortality. OBJECTIVE To study the risk and occurrence of infection in Egyptian SLE patients and to determine its characteristics. METHODS A total of 200 SLE patients were followed up for 1 year at monthly intervals, undergoing clinical and laboratory evaluation. Disease activity was assessed by SLE disease activity measurement (SLAM) score. Infections were diagnosed on basis of clinical findings, medical opinion, positive blood and urine cultures, Gram stain results, and specific serological assays as measurement of CMV and EBV antibodies. RESULTS A total of 55% of patients developed infection, 45% had one infection, and the rest had multiple infection episodes. Total number of infections was 233 infections/year, 47.2% were major and 52.8% were minor infections. Urinary tract was the most commonly involved site with bacterial infection being the commonest isolated organism (46.4%), and E. coli the commonest isolated bacteria (14.2%). There were 51 episodes caused by systemic viral infection (CMV in 25, EBV in 22, HCV in 3, and 1 in HBV). CONCLUSION There is a high rate of infection among SLE patients. Disease activity, leukopenia, high CRP level, positive anti-dsDNA, consumed C3, and cyclophosphamide therapy are independent risk factors for infection in SLE. PMID:25125988

  7. The zta transactivator involved in induction of lytic cycle gene expression in Epstein-Barr virus-infected lymphocytes binds to both AP-1 and ZRE sites in target promoter and enhancer regions.

    PubMed Central

    Lieberman, P M; Hardwick, J M; Sample, J; Hayward, G S; Hayward, S D

    1990-01-01

    The BZLF1 or zta immediate-early gene of Epstein-Barr virus (EBV) encodes a 33-kilodalton phosphorylated nuclear protein that is a specific transcriptional activator of the EBV lytic cycle when introduced into latently infected B lymphocytes. We have shown previously that the divergent EBV DSL target promoter contains two zta-response regions, one within the minimal promoter and the other in an upstream lymphocyte-dependent enhancer region. In this study, we used footprinting and gel mobility retardation assays to reveal that bacterially synthesized Zta fusion proteins bound directly to six TGTGCAA-like motifs within DSL. Four of the Zta-binding sites lay adjacent to cellular TATA and CAAT factor-binding sites within the minimal promoter, and two mapped within the enhancer region. Single-copy oligonucleotides containing these Zta-binding sites conferred Zta responsiveness to heterologous promoters. In addition, the Zta protein, which possesses a similar basic domain to the conserved DNA-binding region of the c-Fos, c-Jun, GCN4, and CREB protein family, proved to bind directly to the consensus AP-1 site in the collagenase 12-O-tetradecanoylphorbol-13-acetate response element. Cotransfection with zta also trans activated a target reporter gene containing inserted wild-type 12-O-tetradecanoylphorbol-13-acetate response element oligonucleotides. Cellular AP-1 binding activity proved to be low in latently EBV-infected Raji cells but was induced (together with the Zta protein) after activation of the lytic cycle with 12-O-tetradecanoylphorbol-13-acetate. We conclude that EBV may have captured and modified a cellular gene encoding a c-jun-like DNA-binding protein during its evolutionary divergence from other herpesviruses and that this protein is used to specifically redirect transcriptional activity toward expression of EBV lytic-cycle genes in infected cells. Images PMID:2154599

  8. Nucleophosmin contributes to the transcriptional activation function of the Epstein-Barr virus EBNA1 protein.

    PubMed

    Malik-Soni, Natasha; Frappier, Lori

    2014-02-01

    The Epstein-Barr virus (EBV) EBNA1 protein plays important roles in latent infection, including transcriptional activation of EBV latency genes by binding to the family-of-repeats (FR) element. Through a proteomic approach, we previously identified an interaction between EBNA1 and the histone chaperone nucleophosmin. Here we show that the EBNA1-nucleophosmin interaction is direct and requires the Gly-Arg-rich sequences that contribute to transactivation. Additionally, nucleophosmin is recruited by EBNA1 to the FR element and is required for EBNA1-mediated transcriptional activation.

  9. Chronic active Epstein-Barr virus infection with cutaneous and sinus lymphoproliferation in a white female patient with 25 years' follow-up: an original case report.

    PubMed

    Picard, C; Gouarin, S; Comoz, F; Barreau, M; Verneuil, L; Troussard, X; Dompmartin, A

    2015-11-01

    Chronic active Epstein-Barr virus infection (CAEBV) is characterized by chronic infectious mononucleosis-like symptoms associated with very high viral load, as assessed by quantitative polymerase chain reaction. We present an unusual case in a French woman who was followed up over 25 years with cutaneous and sinus lymphoproliferation. This white woman presented with a long history of recurrent cutaneous necrotic papules of the skin, which started during childhood and healed spontaneously with depressed scars. The lesions spread to the left maxillary sinus and were associated with hepatomegaly and splenomegaly with no other visceral locations. Pathological examination of the skin and sinus revealed a dermal monoclonal T-cell lymphoproliferative disorder, CD7(+) and CD20(-) , with no epidermotropism. T-cell receptor rearrangement was positive, showing the monoclonality from the first biopsy. This T-cell proliferation was positive for EBV-encoded small RNA and was associated with a high EBV viral load. Since then, the patient has been in good health, despite a permanently high EBV viral load. Hydroa vacciniforme (HV)-like lymphoma and natural killer/T-cell lymphoma were discussed, but none really fit our case. Natural killer cell lymphoma was ruled out because of the indolent course, but sinus lesions do not exist in HV-like lymphoma. A therapeutic approach is difficult because of the coexistence of viral infection and monoclonal T-cell proliferation. Chemotherapy is not efficient and induces immunosuppression, which may worsen the prognosis. Although rituximab may have an immunomodulatory function, it was not effective in our case. PMID:26148205

  10. Basophil activation by mosquito extracts in patients with hypersensitivity to mosquito bites.

    PubMed

    Sakakibara, Yasuhisa; Wada, Taizo; Muraoka, Masahiro; Matsuda, Yusuke; Toma, Tomoko; Yachie, Akihiro

    2015-08-01

    Hypersensitivity to mosquito bites (HMB) is a cutaneous disorder belonging to the group of Epstein-Barr virus (EBV)-associated T/natural killer (NK)-cell lymphoproliferative diseases, and is primarily mediated by EBV-infected NK cells. It is characterized by intense local skin reactions accompanied by general symptoms after mosquito bites, and infiltration of EBV-infected NK cells into the bite sites. However, the mechanisms underlying these reactions have not been fully examined. We recently described the activation of circulating basophils by mosquito extracts in vitro in a patient with HMB. To further investigate this finding, we studied four additional patients with HMB. All patients showed typical clinical features of HMB after mosquito bites and they had NK lymphocytosis and high peripheral blood EBV DNA loads. We found evidence of EBV infection in NK cells through in situ hybridization that detected EBV-encoded small RNA-1, and flow cytometry showed HLA-DR expression on almost all NK cells. Basophil activation tests with the extracts of epidemic mosquitoes Culex pipiens pallens and Aedes albopictus showed positive responses to one or both extracts in all samples from patients with HMB, suggesting the presence of mosquito antigen-specific IgE and its binding to basophils. In particular, the extract of Aedes albopictus was able to activate basophils in all available patient samples. These results indicate that basophils and/or mast cells activated by mosquito bites may be involved in initiation and development of severe skin reactions to mosquito bites in HMB.

  11. Epstein-Barr Virus and Human Papillomavirus Infections and Genotype Distribution in Head and Neck Cancers

    PubMed Central

    Deng, Zeyi; Uehara, Takayuki; Maeda, Hiroyuki; Hasegawa, Masahiro; Matayoshi, Sen; Kiyuna, Asanori; Agena, Shinya; Pan, Xiaoli; Zhang, Chunlin; Yamashita, Yukashi; Xie, Minqiang; Suzuki, Mikio

    2014-01-01

    Objective To investigate the prevalence, genotypes, and prognostic values of Epstein-Barr virus (EBV) and human papillomavirus (HPV) infections in Japanese patients with different types of head and neck cancer (HNC). Methods and Materials HPV and EBV DNA, EBV genotypes and LMP-1 variants, and HPV mRNA expression were detected by PCR from fresh-frozen HNC samples. HPV genotypes were determined by direct sequencing, and EBV encoded RNA (EBER) was examined by in situ hybridization. Results Of the 209 HNC patients, 63 (30.1%) had HPV infection, and HPV-16 was the most common subtype (86.9%). HPV E6/E7 mRNA expression was found in 23 of 60 (38.3%) HPV DNA-positive cases detected. The site of highest prevalence of HPV was the oropharynx (45.9%). Among 146 (69.9%) HNCs in which EBV DNA was identified, 107 (73.3%) and 27 (18.5%) contained types A and B, respectively, and 124 (84.9%) showed the existence of del-LMP-1. However, only 13 (6.2%) HNCs were positive for EBER, 12 (92.3%) of which derived from the nasopharynx. Co-infection of HPV and EBER was found in only 1.0% of HNCs and 10.0% of NPCs. Kaplan-Meier survival analysis showed significantly better disease-specific and overall survival in the HPV DNA+/mRNA+ oropharyngeal squamous cell carcinoma (OPC) patients than in the other OPC patients (P = 0.027 and 0.017, respectively). Multivariate analysis showed that stage T1–3 (P = 0.002) and HPV mRNA-positive status (P = 0.061) independently predicted better disease-specific survival. No significant difference in disease-specific survival was found between the EBER-positive and -negative NPC patients (P = 0.155). Conclusions Our findings indicate that co-infection with HPV and EBV is rare in HNC. Oropharyngeal SCC with active HPV infection was related to a highly favorable outcome, while EBV status was not prognostic in the NPC cohort. PMID:25405488

  12. Epstein–Barr virus infection is not a characteristic feature of multiple sclerosis brain

    PubMed Central

    Willis, Simon N.; Stadelmann, Christine; Rodig, Scott J.; Caron, Tyler; Gattenloehner, Stefan; Mallozzi, Scott S.; Roughan, Jill E.; Almendinger, Stefany E.; Blewett, Megan M.; Brück, Wolfgang; Hafler, David A.

    2009-01-01

    Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system (CNS) that is thought to be caused by a combination of genetic and environmental factors. To date, considerable evidence has associated Epstein–Barr virus (EBV) infection with disease development. However, it remains controversial whether EBV infects multiple sclerosis brain and contributes directly to CNS immunopathology. To assess whether EBV infection is a characteristic feature of multiple sclerosis brain, a large cohort of multiple sclerosis specimens containing white matter lesions (nine adult and three paediatric cases) with a heterogeneous B cell infiltrate and a second cohort of multiple sclerosis specimens (12 cases) that included B cell infiltration within the meninges and parenchymal B cell aggregates, were examined for EBV infection using multiple methodologies including in situ hybridization, immunohistochemistry and two independent real-time polymerase chain reaction (PCR) methodologies that detect genomic EBV or the abundant EBV encoded RNA (EBER) 1, respectively. We report that EBV could not be detected in any of the multiple sclerosis specimens containing white matter lesions by any of the methods employed, yet EBV was readily detectable in multiple Epstein–Barr virus-positive control tissues including several CNS lymphomas. Furthermore, EBV was not detected in our second cohort of multiple sclerosis specimens by in situ hybridization. However, our real-time PCR methodologies, which were capable of detecting very few EBV infected cells, detected EBV at low levels in only 2 of the 12 multiple sclerosis meningeal specimens examined. Our finding that CNS EBV infection was rare in multiple sclerosis brain indicates that EBV infection is unlikely to contribute directly to multiple sclerosis brain pathology in the vast majority of cases. PMID:19638446

  13. Genome-Wide DNA Methylation as an Epigenetic Consequence of Epstein-Barr Virus Infection of Immortalized Keratinocytes

    PubMed Central

    Birdwell, Christine E.; Queen, Krista J.; Kilgore, Phillip C. S. R.; Rollyson, Phoebe; Trutschl, Marjan; Cvek, Urska

    2014-01-01

    ABSTRACT The oral cavity is a persistent reservoir for Epstein-Barr virus (EBV) with lifelong infection of resident epithelial and B cells. Infection of these cell types results in distinct EBV gene expression patterns regulated by epigenetic modifications involving DNA methylation and chromatin structure. Regulation of EBV gene expression relies on viral manipulation of the host epigenetic machinery that may result in long-lasting host epigenetic reprogramming. To identify epigenetic events following EBV infection, a transient infection model was established to map epigenetic changes in telomerase-immortalized oral keratinocytes. EBV-infected oral keratinocytes exhibited a predominantly latent viral gene expression program with some lytic or abortive replication. Calcium and methylcellulose-induced differentiation was delayed in EBV-positive clones and in clones that lost EBV compared to uninfected controls, indicating a functional consequence of EBV epigenetic modifications. Analysis of global cellular DNA methylation identified over 13,000 differentially methylated CpG residues in cells exposed to EBV compared to uninfected controls, with CpG island hypermethylation observed at several cellular genes. Although the vast majority of the DNA methylation changes were silent, 65 cellular genes that acquired CpG methylation showed altered transcript levels. Genes with increased transcript levels frequently acquired DNA methylation within the gene body while those with decreased transcript levels acquired DNA methylation near the transcription start site. Treatment with the DNA methyltransferase inhibitor, decitabine, restored expression of some hypermethylated genes in EBV-infected and EBV-negative transiently infected clones. Overall, these observations suggested that EBV infection of keratinocytes leaves a lasting epigenetic imprint that can enhance the tumorigenic phenotype of infected cells. IMPORTANCE Here, we show that EBV infection of oral keratinocytes led to

  14. Characterization of EBV-related lymphoproliferative lesions arising in donor lymphocytes of transplanted human tumor tissues in the NOG mouse.

    PubMed

    Fujii, Etsuko; Kato, Atsuhiko; Chen, Yu Jau; Matsubara, Koichi; Ohnishi, Yasuyuki; Suzuki, Masami

    2014-01-01

    Human tumor tissue line models established in the severely immunodeficient NOD.Cg-Prkdc(scid) Il2rg(tm1Sug)/Jic (NOD/Shi-scid, IL-2Rγ(null) or NOG) mouse are important tools for oncology research. During the establishment process, a lymphoproliferative lesion (LPL) that replaces the original tumor cells in the site of transplantation occurs. In the present study, we studied the impact of the LPL on the establishment process and the characteristics of the lesion, investigated the systemic distribution of the lesion in the mouse, and evaluated the potential of a simple identification method. The incidence of the lesion varied among tumor types, and the lesion was found to be the leading cause of unsuccessful establishment with gastric and colorectal cancer. The lesion consisted of a varying population of proliferating lymphoid cells that expressed CD20. The cells were positive for Epstein-Barr virus (EBV)-related antigens, and EBV DNA was detected. There was systemic distribution of the lesion within the NOG mouse, and the most consistent gross finding was splenomegaly. Additionally, identification of LPL-affected cases was possible by detecting splenomegaly in the 1st and 2nd generation mice at necropsy. From our findings the lesion was judged to arise from EBV-infected B cells originating from the donor, and monitoring splenomegaly at necropsy was thought effective as a simple method for identifying the lesion at an early stage of the establishment process.

  15. Statin-induced changes in gene expression in EBV-transformed and native B-cells.

    PubMed

    Bolotin, Eugene; Armendariz, Angela; Kim, Kyungpil; Heo, Seok-Jin; Boffelli, Dario; Tantisira, Kelan; Rotter, Jerome I; Krauss, Ronald M; Medina, Marisa W

    2014-03-01

    Human lymphoblastoid cell lines (LCLs), generated through Epstein-Barr Virus (EBV) transformation of B-lymphocytes (B-cells), are a commonly used model system for identifying genetic influences on human diseases and on drug responses. We have previously used LCLs to examine the cellular effects of genetic variants that modulate the efficacy of statins, the most prescribed class of cholesterol-lowering drugs used for the prevention and treatment of cardiovascular disease. However, statin-induced gene expression differences observed in LCLs may be influenced by their transformation, and thus differ from those observed in native B-cells. To assess this possibility, we prepared LCLs and purified B-cells from the same donors, and compared mRNA profiles after 24 h incubation with simvastatin (2 µm) or sham buffer. Genes involved in cholesterol metabolism were similarly regulated between the two cell types under both the statin and sham-treated conditions, and the statin-induced changes were significantly correlated. Genes whose expression differed between the native and transformed cells were primarily implicated in cell cycle, apoptosis and alternative splicing. We found that ChIP-seq signals for MYC and EBNA2 (an EBV transcriptional co-activator) were significantly enriched in the promoters of genes up-regulated in the LCLs compared with the B-cells, and could be involved in the regulation of cell cycle and alternative splicing. Taken together, the results support the use of LCLs for the study of statin effects on cholesterol metabolism, but suggest that drug effects on cell cycle, apoptosis and alternative splicing may be affected by EBV transformation. This dataset is now uploaded to GEO at the accession number GSE51444.

  16. Human cytomegalovirus and Epstein-Barr virus infection in inflammatory bowel disease: Need for mucosal viral load measurement

    PubMed Central

    Ciccocioppo, Rachele; Racca, Francesca; Paolucci, Stefania; Campanini, Giulia; Pozzi, Lodovica; Betti, Elena; Riboni, Roberta; Vanoli, Alessandro; Baldanti, Fausto; Corazza, Gino Roberto

    2015-01-01

    AIM: To evaluate the best diagnostic technique and risk factors of the human Cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) infection in inflammatory bowel disease (IBD). METHODS: A cohort of 40 IBD patients (17 refractory) and 40 controls underwent peripheral blood and endoscopic colonic mucosal sample harvest. Viral infection was assessed by quantitative real-time polymerase chain reaction and immunohistochemistry, and correlations with clinical and endoscopic indexes of activity, and risk factors were investigated. RESULTS: All refractory patients carried detectable levels of HCMV and/or EBV mucosal load as compared to 13/23 (56.5%) non-refractory and 13/40 (32.5%) controls. The median DNA value was significantly higher in refractory (HCMV 286 and EBV 5.440 copies/105 cells) than in non-refractory (HCMV 0 and EBV 6 copies/105 cells; P < 0.05 and < 0.001) IBD patients and controls (HCMV and EBV 0 copies/105 cells; P < 0.001 for both). Refractory patients showed DNA peak values ≥ 103 copies/105 cells in diseased mucosa in comparison to non-diseased mucosa (P < 0.0121 for HCMV and < 0.0004 for EBV), while non-refractory patients and controls invariably displayed levels below this threshold, thus allowing us to differentiate viral colitis from mucosal infection. Moreover, the mucosal load positively correlated with the values found in the peripheral blood, whilst no correlation with the number of positive cells at immunohistochemistry was found. Steroid use was identified as a significant risk factor for both HCMV (P = 0.018) and EBV (P = 0.002) colitis. Finally, a course of specific antiviral therapy with ganciclovir was successful in all refractory patients with HCMV colitis, whilst refractory patients with EBV colitis did not show any improvement despite steroid tapering and discontinuation of the other medications. CONCLUSION: Viral colitis appeared to contribute to mucosal lesions in refractory IBD, and its correct diagnosis and management require

  17. Role of NF-kappa B in cell survival and transcription of latent membrane protein 1-expressing or Epstein-Barr virus latency III-infected cells.

    PubMed

    Cahir-McFarland, Ellen D; Carter, Kara; Rosenwald, Andreas; Giltnane, Jena M; Henrickson, Sarah E; Staudt, Louis M; Kieff, Elliott

    2004-04-01

    Epstein-Barr virus (EBV) latency III infection converts B lymphocytes into lymphoblastoid cell lines (LCLs) by expressing EBV nuclear and membrane proteins, EBNAs, and latent membrane proteins (LMPs), which regulate transcription through Notch and tumor necrosis factor receptor pathways. The role of NF-kappa B in LMP1 and overall EBV latency III transcriptional effects was investigated by treating LCLs with BAY11-7082 (BAY11). BAY11 rapidly and irreversibly inhibited NF-kappa B, decreased mitochondrial membrane potential, induced apoptosis, and altered LCL gene expression. BAY11 effects were similar to those of an NF-kappa B inhibitor, Delta N-I kappa B alpha, in effecting decreased JNK1 expression and in microarray analyses. More than 80% of array elements that decreased with Delta N-I kappa B alpha expression decreased with BAY11 treatment. Newly identified NF-kappa B-induced, LMP1-induced, and EBV-induced genes included pleckstrin, Jun-B, c-FLIP, CIP4, and I kappa B epsilon. Of 776 significantly changed array elements, 134 were fourfold upregulated in EBV latency III, and 74 were fourfold upregulated with LMP1 expression alone, whereas only 28 were more than fourfold downregulated by EBV latency III. EBV latency III-regulated gene products mediate cell migration (EBI2, CCR7, RGS1, RANTES, MIP1 alpha, MIP1 beta, CXCR5, and RGS13), antigen presentation (major histocompatibility complex proteins and JAW1), mitogen-activated protein kinase pathway (DUSP5 and p62Dok), and interferon (IFN) signaling (IFN-gamma R alpha, IRF-4, and STAT1). Comparison of EBV latency III LCL gene expression to immunoglobulin M (IgM)-stimulated B cells, germinal-center B cells, and germinal-center-derived lymphomas clustered LCLs with IgM-stimulated B cells separately from germinal-center cells or germinal-center lymphoma cells. Expression of IRF-2, AIM1, ASK1, SNF2L2, and components of IFN signaling pathways further distinguished EBV latency III-infected B cells from IgM-stimulated or

  18. Human cytomegalovirus and Epstein–Barr virus inhibit oral bacteria-induced macrophage activation and phagocytosis

    PubMed Central

    Lin, Y.-L.; Li, M.

    2016-01-01

    Introduction Periodontal disease is an inflammatory condition caused by periodontal microorganisms. Viruses such as human cytomegalovirus (HCMV) and Epstein–Barr virus (EBV) are associated with certain types of periodontal disease, but their roles in promoting the disease are unclear. Because both viruses infect human macrophages, cells which play key roles in the clearance of pathogenic bacteria, it is likely that the viruses alter the functional capacity of macrophages by inhibiting their defense mechanisms against invading pathogens. Methods Macrophages preinfected with HCMV or EBV were evaluated following stimulation by selected oral bacteria. Bacteria-induced macrophage activation was assayed by measuring the levels of tumor necrosis factor-α (TNF-α) produced in the media, and phagocytic activity was analysed by a phagocytosis assay with fluorescein isothiocyanate-labeled bacteria. The virus-infected macrophages were also subjected to semi-quantitative polymerase chain reaction to measure the expression of toll-like receptor 9, which is involved in the activation of phagocytosis-related pathways. Results Both HCMV and EBV significantly diminished the TNF-α production typically induced by oral bacteria, inhibited the phagocytic activity of macrophages, and downregulated the expression of toll-like receptor 9. Conclusion Infection by HCMV or EBV inhibits the functional ability of macrophages to respond to bacterial challenge, thereby suggesting their pathogenic role in the development of periodontal disease. PMID:19416455

  19. MAIT cells are activated during human viral infections.

    PubMed

    van Wilgenburg, Bonnie; Scherwitzl, Iris; Hutchinson, Edward C; Leng, Tianqi; Kurioka, Ayako; Kulicke, Corinna; de Lara, Catherine; Cole, Suzanne; Vasanawathana, Sirijitt; Limpitikul, Wannee; Malasit, Prida; Young, Duncan; Denney, Laura; Moore, Michael D; Fabris, Paolo; Giordani, Maria Teresa; Oo, Ye Htun; Laidlaw, Stephen M; Dustin, Lynn B; Ho, Ling-Pei; Thompson, Fiona M; Ramamurthy, Narayan; Mongkolsapaya, Juthathip; Willberg, Christian B; Screaton, Gavin R; Klenerman, Paul

    2016-01-01

    Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus. This activation-driving cytokine release and Granzyme B upregulation-is TCR-independent but dependent on IL-18 in synergy with IL-12, IL-15 and/or interferon-α/β. IL-18 levels and MAIT cell activation correlate with disease severity in acute dengue infection. Furthermore, HCV treatment with interferon-α leads to specific MAIT cell activation in vivo in parallel with an enhanced therapeutic response. Moreover, TCR-independent activation of MAIT cells leads to a reduction of HCV replication in vitro mediated by IFN-γ. Together these data demonstrate MAIT cells are activated following viral infections, and suggest a potential role in both host defence and immunopathology. PMID:27337592

  20. Associations between EBV and CMV Seropositivity, Early Exposures, and Gut Microbiota in a Prospective Birth Cohort: A 10-Year Follow-up

    PubMed Central

    Carvalho-Queiroz, Claudia; Johansson, Maria A.; Persson, Jan-Olov; Jörtsö, Evelina; Kjerstadius, Torbjörn; Nilsson, Caroline; Saghafian-Hedengren, Shanie; Sverremark-Ekström, Eva

    2016-01-01

    Early-life infections with persistent Epstein–Barr virus (EBV) and cytomegalovirus (CMV) are delayed in affluent countries, probably due to alterations in early environmental exposures, such as maternal age, siblings, and day-care attendance. We have previously reported that the timing of EBV and CMV contraction is related both to allergic sensitization and changes in functional competence of immune cells, while the presence/absence of lactobacilli [Lactobacillus (L.) casei, L. paracasei, and L. rhamnosus] or Staphylococcus (S.) aureus in feces is related to the risk for allergy. Here, we used the same prospective longitudinal birth cohort of children to investigate early-life environmental exposures and their influence on EBV and CMV contraction over time. Since gut microbes also belong to this category of early exposures, we investigated their association with herpesvirus contraction. Our results show that these two viruses are acquired with different kinetics and that EBV and CMV seroprevalence at 10 years of age was 47 and 57%, respectively. We also observed that a delayed EBV or CMV infection was associated with older maternal age [time ratio (TR) 1.14, 95% confidence interval (CI) 1.07–1.21, Padj < 0.001 and TR 1.09, CI 1.03–1.16, Padj = 0.008, respectively]. Further, we present the novel finding that S. aureus colonization reduced the time to CMV acquisition (TR 0.21, CI 0.06–0.78, Padj = 0.02). Together, these findings suggest that there is a relationship between timing of herpesvirus acquisition and early-life immune modulating exposures, which interestingly also includes the early infant gut microbiota.

  1. Associations between EBV and CMV Seropositivity, Early Exposures, and Gut Microbiota in a Prospective Birth Cohort: A 10-Year Follow-up

    PubMed Central

    Carvalho-Queiroz, Claudia; Johansson, Maria A.; Persson, Jan-Olov; Jörtsö, Evelina; Kjerstadius, Torbjörn; Nilsson, Caroline; Saghafian-Hedengren, Shanie; Sverremark-Ekström, Eva

    2016-01-01

    Early-life infections with persistent Epstein–Barr virus (EBV) and cytomegalovirus (CMV) are delayed in affluent countries, probably due to alterations in early environmental exposures, such as maternal age, siblings, and day-care attendance. We have previously reported that the timing of EBV and CMV contraction is related both to allergic sensitization and changes in functional competence of immune cells, while the presence/absence of lactobacilli [Lactobacillus (L.) casei, L. paracasei, and L. rhamnosus] or Staphylococcus (S.) aureus in feces is related to the risk for allergy. Here, we used the same prospective longitudinal birth cohort of children to investigate early-life environmental exposures and their influence on EBV and CMV contraction over time. Since gut microbes also belong to this category of early exposures, we investigated their association with herpesvirus contraction. Our results show that these two viruses are acquired with different kinetics and that EBV and CMV seroprevalence at 10 years of age was 47 and 57%, respectively. We also observed that a delayed EBV or CMV infection was associated with older maternal age [time ratio (TR) 1.14, 95% confidence interval (CI) 1.07–1.21, Padj < 0.001 and TR 1.09, CI 1.03–1.16, Padj = 0.008, respectively]. Further, we present the novel finding that S. aureus colonization reduced the time to CMV acquisition (TR 0.21, CI 0.06–0.78, Padj = 0.02). Together, these findings suggest that there is a relationship between timing of herpesvirus acquisition and early-life immune modulating exposures, which interestingly also includes the early infant gut microbiota. PMID:27630978

  2. Associations between EBV and CMV Seropositivity, Early Exposures, and Gut Microbiota in a Prospective Birth Cohort: A 10-Year Follow-up.

    PubMed

    Carvalho-Queiroz, Claudia; Johansson, Maria A; Persson, Jan-Olov; Jörtsö, Evelina; Kjerstadius, Torbjörn; Nilsson, Caroline; Saghafian-Hedengren, Shanie; Sverremark-Ekström, Eva

    2016-01-01

    Early-life infections with persistent Epstein-Barr virus (EBV) and cytomegalovirus (CMV) are delayed in affluent countries, probably due to alterations in early environmental exposures, such as maternal age, siblings, and day-care attendance. We have previously reported that the timing of EBV and CMV contraction is related both to allergic sensitization and changes in functional competence of immune cells, while the presence/absence of lactobacilli [Lactobacillus (L.) casei, L. paracasei, and L. rhamnosus] or Staphylococcus (S.) aureus in feces is related to the risk for allergy. Here, we used the same prospective longitudinal birth cohort of children to investigate early-life environmental exposures and their influence on EBV and CMV contraction over time. Since gut microbes also belong to this category of early exposures, we investigated their association with herpesvirus contraction. Our results show that these two viruses are acquired with different kinetics and that EBV and CMV seroprevalence at 10 years of age was 47 and 57%, respectively. We also observed that a delayed EBV or CMV infection was associated with older maternal age [time ratio (TR) 1.14, 95% confidence interval (CI) 1.07-1.21, P adj < 0.001 and TR 1.09, CI 1.03-1.16, P adj = 0.008, respectively]. Further, we present the novel finding that S. aureus colonization reduced the time to CMV acquisition (TR 0.21, CI 0.06-0.78, P adj = 0.02). Together, these findings suggest that there is a relationship between timing of herpesvirus acquisition and early-life immune modulating exposures, which interestingly also includes the early infant gut microbiota. PMID:27630978

  3. Identification of the critical attribute(s) of EBV gp350 antigen required for elicitation of a neutralizing antibody response in vivo.

    PubMed

    Servat, Esteban; Ro, Bodrey W; Cayatte, Corinne; Gemmell, Lorraine; Barton, Chris; Rao, Eileen; Lin, Rui; Zuo, Fengrong; Woo, Jennifer C; Hayes, Gregory M

    2015-11-27

    Vaccine prophylaxis with EBV glycoprotein 350 (gp350) subunit plus adjuvant has been demonstrated clinically to protect individuals against infectious mononucleosis (IM), but the specifications of the antigen required to elicit this protection has remained largely theoretical. Previous studies have shown that antibodies to gp350 comprise the principle component of EBV-neutralizing sera. Further, a murine monoclonal antibody against gp350 (clone 72A1) is able to prevent infection by the virus both in vitro and in vivo. In the present study, we identify the 72A1 epitope on recombinant gp350 antigen as the site required for binding to CD21 on human B cells. We also identify the need for conformational-dependence of the antigen to generate EBV-neutralizing antibodies in vivo. Further, we have characterized the glycosylation status and antigenicity profiles of both native and denatured CHO-produced soluble gp350 as well as non-glycosylated protein produced in Escherichia coli. Collectively our in vitro and in vivo data demonstrate the requirement for a conformationally accessible 72A1 epitope on gp350 to elicit EBV-neutralizing responses, and establish this as a critical attribute of this vaccine antigen. These data provide direction for commercial vaccine development, as the absence of this epitope on either E. coli-expressed or denatured gp350, may limit production and purification options for the antigen. PMID:26485517

  4. MAIT cells are activated during human viral infections

    PubMed Central

    van Wilgenburg, Bonnie; Scherwitzl, Iris; Hutchinson, Edward C.; Leng, Tianqi; Kurioka, Ayako; Kulicke, Corinna; de Lara, Catherine; Cole, Suzanne; Vasanawathana, Sirijitt; Limpitikul, Wannee; Malasit, Prida; Young, Duncan; Denney, Laura; Barnes, Eleanor; Ball, Jonathan; Burgess, Gary; Cooke, Graham; Dillon, John; Gore, Charles; Foster, Graham; Guha, Neil; Halford, Rachel; Herath, Cham; Holmes, Chris; Howe, Anita; Hudson, Emma; Irving, William; Khakoo, Salim; Koletzki, Diana; Martin, Natasha; Mbisa, Tamyo; McKeating, Jane; McLauchlan, John; Miners, Alec; Murray, Andrea; Shaw, Peter; Simmonds, Peter; Spencer, Chris; Targett-Adams, Paul; Thomson, Emma; Vickerman, Peter; Zitzmann, Nicole; Moore, Michael D.; Fabris, Paolo; Giordani, Maria Teresa; Oo, Ye Htun; Laidlaw, Stephen M.; Dustin, Lynn B.; Ho, Ling-Pei; Thompson, Fiona M.; Ramamurthy, Narayan; Mongkolsapaya, Juthathip; Willberg, Christian B.; Screaton, Gavin R.; Klenerman, Paul

    2016-01-01

    Mucosal-associated invariant T (MAIT) cells are abundant in humans and recognize bacterial ligands. Here, we demonstrate that MAIT cells are also activated during human viral infections in vivo. MAIT cells activation was observed during infection with dengue virus, hepatitis C virus and influenza virus. This activation—driving cytokine release and Granzyme B upregulation—is TCR-independent but dependent on IL-18 in synergy with IL-12, IL-15 and/or interferon-α/β. IL-18 levels and MAIT cell activation correlate with disease severity in acute dengue infection. Furthermore, HCV treatment with interferon-α leads to specific MAIT cell activation in vivo in parallel with an enhanced therapeutic response. Moreover, TCR-independent activation of MAIT cells leads to a reduction of HCV replication in vitro mediated by IFN-γ. Together these data demonstrate MAIT cells are activated following viral infections, and suggest a potential role in both host defence and immunopathology. PMID:27337592

  5. [History of resaerch on Epstein-Barr virus--target cells of infection, and disease].

    PubMed

    Ohga, Shouichi

    2014-01-01

    Half a century has passed since Epstein-Barr virus (EBV) particles were isolated from the cultured lymphoblasts of Burkitt lymphoma. During the period, molecular biology, hematology/immunology, and transplantation medicine made amazing progress, that clarified the mode of infection and pathophysiology of the virus in human diseases. Research strategies on the relationship between EBV and human have expanded to the epidemiology, structures and functions of both genomes, regulatory genes including microRNA, and the nature of epigenetics. Although no animal models of EBV infection long hampered the completion of in vivo experiments, humanized mice have broken through a barrier of in vitro study on EBV-infected cell lines. Our understanding of the life cycle of EBV has continued to deepen about the infection via the CD21 receptor expressed on B cells, the latency, reactivation/reinfection, and transformation, and also the dynamics of T-cell immune response and the intracellular immunosurveillance beyond acquired and innate immunity. On the other hand, the disease entity of life-threatening lymphoproliferative disease of EBV-infected T cells or NK cells is on controversial. The other parts of this special issue include the recent topics of the basic and clinical researches of EBV as the oncogenic virus. Then, we herewith overview the research history of EBV with special reference to the infected cells and host immune responses in EBV-associated diseases. PMID:25765982

  6. Macaque Homologs of EBV and KSHV Show Uniquely Different Associations with Simian AIDS-related Lymphomas

    PubMed Central

    Bruce, A. Gregory; Bielefeldt-Ohmann, Helle; Barcy, Serge; Bakke, Angela M.; Lewis, Patrick; Tsai, Che-Chung; Murnane, Robert D.; Rose, Timothy M.

    2012-01-01

    Two gammaherpesviruses, Epstein-Barr virus (EBV) (Lymphocryptovirus genus) and Kaposi's sarcoma-associated herpesvirus (KSHV) (Rhadinovirus genus) have been implicated in the etiology of AIDS-associated lymphomas. Homologs of these viruses have been identified in macaques and other non-human primates. In order to assess the association of these viruses with non-human primate disease, archived lymphoma samples were screened for the presence of macaque lymphocryptovirus (LCV) homologs of EBV, and macaque rhadinoviruses belonging to the RV1 lineage of KSHV homologs or the more distant RV2 lineage of Old World primate rhadinoviruses. Viral loads were determined by QPCR and infected cells were identified by immunolabeling for different viral proteins. The lymphomas segregated into three groups. The first group (n = 6) was associated with SIV/SHIV infections, contained high levels of LCV (1–25 genomes/cell) and expressed the B-cell antigens CD20 or BLA.36. A strong EBNA-2 signal was detected in the nuclei of the neoplastic cells in one of the LCV-high lymphomas, indicative of a type III latency stage. None of the lymphomas in this group stained for the LCV viral capsid antigen (VCA) lytic marker. The second group (n = 5) was associated with D-type simian retrovirus-2 (SRV-2) infections, contained high levels of RV2 rhadinovirus (9–790 genomes/cell) and expressed the CD3 T-cell marker. The third group (n = 3) was associated with SIV/SHIV infections, contained high levels of RV2 rhadinovirus (2–260 genomes/cell) and was negative for both CD20 and CD3. In both the CD3-positive and CD3/CD20-negative lymphomas, the neoplastic cells stained strongly for markers of RV2 lytic replication. None of the lymphomas had detectable levels of retroperitoneal fibromatosis herpesvirus (RFHV), the macaque RV1 homolog of KSHV. Our data suggest etiological roles for both lymphocryptoviruses and RV2 rhadinoviruses in the development of simian AIDS-associated lymphomas and

  7. EBV-negative monomorphic B-cell post-transplant lymphoproliferative disorders are pathologically distinct from EBV-positive cases and frequently contain TP53 mutations.

    PubMed

    Courville, Elizabeth L; Yohe, Sophia; Chou, David; Nardi, Valentina; Lazaryan, Aleksandr; Thakral, Beenu; Nelson, Andrew C; Ferry, Judith A; Sohani, Aliyah R

    2016-10-01

    Monomorphic post-transplant lymphoproliferative disorder commonly resembles diffuse large B-cell lymphoma or Burkitt lymphoma, and most are Epstein-Barr virus (EBV) positive. We retrospectively identified 32 cases of monomorphic post-transplant lymphoproliferative disorder from two institutions and evaluated EBV in situ hybridization; TP53 mutation status; p53, CD30, myc, and BCL2 expression by immunohistochemistry; proliferation index by Ki67; and germinal center vs non-germinal center immunophenotype by Hans criteria. Post-transplant lymphoproliferative disorder arose after hematopoietic stem cell transplant in five and solid organ transplant in 27 patients, a median of 4 and 96 months after transplant, respectively (overall median latency 71 months, range 2-295). The most common morphology was diffuse large B-cell lymphoma (28 cases), with three cases of Burkitt lymphoma, and one case of plasmablastic lymphoma. Ten cases (31%) were EBV negative. Of those with the morphology of diffuse large B-cell lymphoma, the EBV-negative cases were more frequently TP53-mutated (P<0.001), p53 positive by immunohistochemistry (P<0.001), CD30 negative (P<0.01), and of germinal center immunophenotype (P=0.01) compared with EBV-positive cases. No statistically significant difference in overall survival was identified based on EBV, TP53 mutation status, germinal center vs non-germinal center immunophenotype, or other immunohistochemical parameters evaluated. Patients who died of post-transplant lymphoproliferative disorder were older with a longer latency from time of transplant to diagnosis (P<0.05). Our study demonstrates that diffuse large B-cell lymphoma-related immunohistochemical prognostic markers have limited relevance in the post-transplant setting and underscores differences between EBV-positive and EBV-negative post-transplant lymphoproliferative disorder in terms of immunophenotype and TP53 mutation frequency, supporting an alternative pathogenesis for EBV-negative post

  8. HLA-A*02:07 Is a Protective Allele for EBV Negative and a Susceptibility Allele for EBV Positive Classical Hodgkin Lymphoma in China

    PubMed Central

    Huang, Xin; Hepkema, Bouke; Nolte, Ilja; Kushekhar, Kushi; Jongsma, Theo; Veenstra, Rianne; Poppema, Sibrand; Gao, Zifen; Visser, Lydia; Diepstra, Arjan; van den Berg, Anke

    2012-01-01

    HLA-A2 protects from EBV+ classical Hodgkin lymphoma (cHL) in Western Europe, but it is unknown whether this protective effect also exists in the Chinese population. We investigated the association of HLA-A2 and specific common and well documented HLA-A2 subtypes with EBV stratified cHL patients (n = 161) from the northern part of China. Quantitative-PCR and sequence-based subtyping was performed to identify HLA-A2 positive samples and their subtypes. 67 (42%) of the cHL patients were EBV+. There were no significant differences in percentages of HLA-A2 positivity between cHL and controls (65% vs 66%) and between EBV+ and EBV− cHL patients (70% vs 61%). The frequency distribution of HLA-A2 subtypes was significantly different between EBV stratified cHL subgroups and controls. This difference was most striking for the HLA-A*02:07 type with a frequency of 38% in EBV+ cHL, 8% in EBV− cHL and 20% in controls. Significant differences were also observed for the HLA-A*02:07, HLA-A2 (non-02:07) and the A2-negative typings between EBV+ cHL vs controls (p = 0.028), EBV− cHL vs controls (p = 0.045) and EBV+ vs EBV− cHL cases (p = 2×10−5). In conclusion, HLA-A*02:07 is a predisposing allele for EBV+ cHL and a protective allele for EBV− cHL in the northern Chinese population. PMID:22355400

  9. The impact of HLA class I and EBV latency-II antigen-specific CD8(+) T cells on the pathogenesis of EBV(+) Hodgkin lymphoma.

    PubMed

    Jones, K; Wockner, L; Brennan, R M; Keane, C; Chattopadhyay, P K; Roederer, M; Price, D A; Cole, D K; Hassan, B; Beck, K; Gottlieb, D; Ritchie, D S; Seymour, J F; Vari, F; Crooks, P; Burrows, S R; Gandhi, M K

    2016-02-01

    In 40% of cases of classical Hodgkin lymphoma (cHL), Epstein-Barr virus (EBV) latency-II antigens [EBV nuclear antigen 1 (EBNA1)/latent membrane protein (LMP)1/LMP2A] are present (EBV(+) cHL) in the malignant cells and antigen presentation is intact. Previous studies have shown consistently that HLA-A*02 is protective in EBV(+) cHL, yet its role in disease pathogenesis is unknown. To explore the basis for this observation, gene expression was assessed in 33 cHL nodes. Interestingly, CD8 and LMP2A expression were correlated strongly and, for a given LMP2A level, CD8 was elevated markedly in HLA-A*02(-) versus HLA-A*02(+) EBV(+) cHL patients, suggesting that LMP2A-specific CD8(+) T cell anti-tumoral immunity may be relatively ineffective in HLA-A*02(-) EBV(+) cHL. To ascertain the impact of HLA class I on EBV latency antigen-specific immunodominance, we used a stepwise functional T cell approach. In newly diagnosed EBV(+) cHL, the magnitude of ex-vivo LMP1/2A-specific CD8(+) T cell responses was elevated in HLA-A*02(+) patients. Furthermore, in a controlled in-vitro assay, LMP2A-specific CD8(+) T cells from healthy HLA-A*02 heterozygotes expanded to a greater extent with HLA-A*02-restricted compared to non-HLA-A*02-restricted cell lines. In an extensive analysis of HLA class I-restricted immunity, immunodominant EBNA3A/3B/3C-specific CD8(+) T cell responses were stimulated by numerous HLA class I molecules, whereas the subdominant LMP1/2A-specific responses were confined largely to HLA-A*02. Our results demonstrate that HLA-A*02 mediates a modest, but none the less stronger, EBV-specific CD8(+) T cell response than non-HLA-A*02 alleles, an effect confined to EBV latency-II antigens. Thus, the protective effect of HLA-A*02 against EBV(+) cHL is not a surrogate association, but reflects the impact of HLA class I on EBV latency-II antigen-specific CD8(+) T cell hierarchies.

  10. Activation of Complement by Cells Infected with Respiratory Syncytial Virus

    PubMed Central

    Smith, Thomas F.; Mcintosh, Kenneth; Fishaut, Mark; Henson, Peter M.

    1981-01-01

    The ability of respiratory syncytial virus (RSV)-infected HEp-2 cells in culture to activate complement was investigated. After incubation of cells with various complement sources and buffer, binding of C3b to surfaces of infected cells was demonstrated by immunofluorescence with a double-staining technique. Nonsyncytial and syncytial (i.e., fused, multinucleated) cells were separately enumerated. Also, lysis of RSV-infected cells was assessed by lactic dehydrogenase release. In this system only RSV-infected cells stained for C3b, and they did so only after incubation with functionally active complement. Blocking of classical pathway activation with ethylenediaminetetraacetic acid diminished the number of infected nonsyncytial cells positively stained for C3b, but had no effect on staining of syncytial cells. Blocking of alternative pathway activation with either zymosan incubation or heat treatment decreased the number of both syncytial and nonsyncytial cells stained for C3b. Decreasing immunoglobulin concentration of the serum used as the complement source also decreased numbers of both cell types stained for C3b. Eliminating specific anti-RSV antibody diminished numbers of both cell types stained for C3b, but staining was not eliminated. Lastly, incubation with functionally active complement markedly increased lactic dehydrogenase release from infected cells. This study demonstrated that RSV-infected nonsyncytial and syncytial cells are able to activate complement by both classical and alternative pathways. Activation of complement by syncytial cells appears to be less dependent on the classical pathway than is activation by nonsyncytial cells, and activation by syncytial cells may require immunoglobulin but not specific antibody. These experiments suggest the possibility of complement activation during respiratory tract infection by RSV. Implications of this are discussed. Images PMID:7263071

  11. MYC activation and BCL2L11 silencing by a tumour virus through the large-scale reconfiguration of enhancer-promoter hubs.

    PubMed

    Wood, C David; Veenstra, Hildegonda; Khasnis, Sarika; Gunnell, Andrea; Webb, Helen M; Shannon-Lowe, Claire; Andrews, Simon; Osborne, Cameron S; West, Michelle J

    2016-01-01

    Lymphomagenesis in the presence of deregulated MYC requires suppression of MYC-driven apoptosis, often through downregulation of the pro-apoptotic BCL2L11 gene (Bim). Transcription factors (EBNAs) encoded by the lymphoma-associated Epstein-Barr virus (EBV) activate MYC and silence BCL2L11. We show that the EBNA2 transactivator activates multiple MYC enhancers and reconfigures the MYC locus to increase upstream and decrease downstream enhancer-promoter interactions. EBNA2 recruits the BRG1 ATPase of the SWI/SNF remodeller to MYC enhancers and BRG1 is required for enhancer-promoter interactions in EBV-infected cells. At BCL2L11, we identify a haematopoietic enhancer hub that is inactivated by the EBV repressors EBNA3A and EBNA3C through recruitment of the H3K27 methyltransferase EZH2. Reversal of enhancer inactivation using an EZH2 inhibitor upregulates BCL2L11 and induces apoptosis. EBV therefore drives lymphomagenesis by hijacking long-range enhancer hubs and specific cellular co-factors. EBV-driven MYC enhancer activation may contribute to the genesis and localisation of MYC-Immunoglobulin translocation breakpoints in Burkitt's lymphoma. PMID:27490482

  12. MYC activation and BCL2L11 silencing by a tumour virus through the large-scale reconfiguration of enhancer-promoter hubs

    PubMed Central

    Wood, C David; Veenstra, Hildegonda; Khasnis, Sarika; Gunnell, Andrea; Webb, Helen M; Shannon-Lowe, Claire; Andrews, Simon; Osborne, Cameron S; West, Michelle J

    2016-01-01

    Lymphomagenesis in the presence of deregulated MYC requires suppression of MYC-driven apoptosis, often through downregulation of the pro-apoptotic BCL2L11 gene (Bim). Transcription factors (EBNAs) encoded by the lymphoma-associated Epstein-Barr virus (EBV) activate MYC and silence BCL2L11. We show that the EBNA2 transactivator activates multiple MYC enhancers and reconfigures the MYC locus to increase upstream and decrease downstream enhancer-promoter interactions. EBNA2 recruits the BRG1 ATPase of the SWI/SNF remodeller to MYC enhancers and BRG1 is required for enhancer-promoter interactions in EBV-infected cells. At BCL2L11, we identify a haematopoietic enhancer hub that is inactivated by the EBV repressors EBNA3A and EBNA3C through recruitment of the H3K27 methyltransferase EZH2. Reversal of enhancer inactivation using an EZH2 inhibitor upregulates BCL2L11 and induces apoptosis. EBV therefore drives lymphomagenesis by hijacking long-range enhancer hubs and specific cellular co-factors. EBV-driven MYC enhancer activation may contribute to the genesis and localisation of MYC-Immunoglobulin translocation breakpoints in Burkitt's lymphoma. DOI: http://dx.doi.org/10.7554/eLife.18270.001 PMID:27490482

  13. Long-term Outcome of Extranodal NK/T Cell Lymphoma Patients Treated With Postremission Therapy Using EBV LMP1 and LMP2a-specific CTLs.

    PubMed

    Cho, Seok-Goo; Kim, Nayoun; Sohn, Hyun-Jung; Lee, Suk Kyeong; Oh, Sang Taek; Lee, Hyun-Joo; Cho, Hyun-Il; Yim, Hyeon Woo; Jung, Seung Eun; Park, Gyeongsin; Oh, Joo Hyun; Choi, Byung-Ock; Kim, Sung Won; Kim, Soo Whan; Chung, Nak Gyun; Lee, Jong Wook; Hong, Young Seon; Kim, Tai-Gyu

    2015-08-01

    Extranodal NK/T-cell lymphoma (ENKTCL) is associated with latent Epstein-Barr virus (EBV) infection and frequent relapse even after complete response (CR) to intensive chemotherapy and radiotherapy. The expression of EBV proteins in the tumor provides targets for adoptive immunotherapy with antigen-specific cytotoxic T cells (CTL). To evaluate the efficacy and safety of EBV latent membrane protein (LMP)-1 and LMP-2a-specific CTLs (LMP1/2a CTLs) stimulated with LMP1/2a RNA-transferred dendritic cells, we treated 10 ENKTCL patients who showed complete response to induction therapy. Patients who completed and responded to chemotherapy, radiotherapy, and/or high-dose therapy followed by stem cell transplantation (HDT/SCT) were eligible to receive eight doses of 2 × 10(7) LMP1/2a CTLs/m(2). Following infusion, there were no immediate or delayed toxicities. The 4-year overall survival (OS) and progression-free survival (PFS) were 100%, and 90% (95% CI: 71.4 to 100%) respectively with a median follow-up of 55·5 months. Circulating IFN-γ secreting LMP1 and LMP2a-specific T cells within the peripheral blood corresponded with decline in plasma EBV DNA levels in patients. Adoptive transfer of LMP1/2a CTLs in ENKTCL patients is a safe and effective postremission therapeutic approach. Further randomized studies will be needed to define the role of EBV-CTLs in preventing relapse of ENKTCL. PMID:26017177

  14. Small Molecule Growth Inhibitors of Human Oncogenic Gammaherpesvirus Infected B-Cells

    PubMed Central

    Dzeng, Richard K.; Jha, Hem Chandra; Lu, Jie; Saha, Abhik; Banerjee, Sagarika; Robertson, Erle S.

    2014-01-01

    Epstein-Barr virus (EBV) and Kaposi’s sarcoma associated herpesvirus (KSHV) are two human gammaherpesviruses associated with a broad spectrum of B-cell lymphomas, most acutely in immuno-compromised populations. However, there are no drugs which specifically target KSHV or EBV-associated lymphomas. To identify small molecules which selectively inhibit the growth of EBV or KSHV-associated B-cell lines, we performed a fluorescence based high-throughput screen on multiple stable GFP expressing virus-infected or uninfected B-cell lines. We identified 40 initial compounds with selective growth inhibition and subsequently determined the 50% growth inhibitory concentrations (GI50) for each drug. We further examined compounds with higher specificity to explore the underlying molecular mechanisms using transcription factor analysis, as well as a sh-RNA based knockdown strategy. Our data identified ten compounds with relatively high efficacy for growth inhibition. Two novel small molecules, NSC#10010 and NSC#65381 were potent growth inhibitors for gammaherpesvirus-associated B-lymphomas through activation of both the NF-κB and c-Myc- mediated signaling pathways. These drugs can serve as potential lead compounds to expand the current therapeutic window against EBV or KSHV associated human B-cell malignancies. PMID:25306391

  15. The Epstein-Barr Virus Glycoprotein gp150 Forms an Immune-Evasive Glycan Shield at the Surface of Infected Cells

    PubMed Central

    Gram, Anna M.; Oosenbrug, Timo; Lindenbergh, Marthe F. S.; Büll, Christian; Comvalius, Anouskha; Dickson, Kathryn J. I.; Wiegant, Joop; Vrolijk, Hans; Lebbink, Robert Jan; Wolterbeek, Ron; Adema, Gosse J.; Griffioen, Marieke; Heemskerk, Mirjam H. M.; Tscharke, David C.; Hutt-Fletcher, Lindsey M.; Ressing, Maaike E.

    2016-01-01

    Cell-mediated immunity plays a key role in host control of viral infection. This is exemplified by life-threatening reactivations of e.g. herpesviruses in individuals with impaired T-cell and/or iNKT cell responses. To allow lifelong persistence and virus production in the face of primed immunity, herpesviruses exploit immune evasion strategies. These include a reduction in viral antigen expression during latency and a number of escape mechanisms that target antigen presentation pathways. Given the plethora of foreign antigens expressed in virus-producing cells, herpesviruses are conceivably most vulnerable to elimination by cell-mediated immunity during the replicative phase of infection. Here, we show that a prototypic herpesvirus, Epstein-Barr virus (EBV), encodes a novel, broadly acting immunoevasin, gp150, that is expressed during the late phase of viral replication. In particular, EBV gp150 inhibits antigen presentation by HLA class I, HLA class II, and the non-classical, lipid-presenting CD1d molecules. The mechanism of gp150-mediated T-cell escape does not depend on degradation of the antigen-presenting molecules nor does it require gp150’s cytoplasmic tail. Through its abundant glycosylation, gp150 creates a shield that impedes surface presentation of antigen. This is an unprecedented immune evasion mechanism for herpesviruses. In view of its likely broader target range, gp150 could additionally have an impact beyond escape of T cell activation. Importantly, B cells infected with a gp150-null mutant EBV displayed rescued levels of surface antigen presentation by HLA class I, HLA class II, and CD1d, supporting an important role for iNKT cells next to classical T cells in fighting EBV infection. At the same time, our results indicate that EBV gp150 prolongs the timespan for producing viral offspring at the most vulnerable stage of the viral life cycle. PMID:27077376

  16. Analysis of Epstein-Barr virus infection models in a series of pediatric carriers from a developing country

    PubMed Central

    Vistarop, Aldana G.; Cohen, Melina; De Matteo, Elena; Preciado, María Victoria; Chabay, Paola A.

    2016-01-01

    Epstein-Barr virus (EBV) is a B lymphotropic human herpesvirus. Two models, germinal center (GC) and direct infection, describe how EBV infects B-cells. Since in Argentina primary infection is mostly subclinical at young ages, children represent an interesting population where to analyze EBV infection, especially considering that most studies are usually performed in adults. Tonsil biopsies from pediatric carriers were studied to describe infection characteristics. EBV+ lymphocytes at the interfollicular region were mainly observed. Latency III pattern in subepithelial (SubEp) lymphocytes was observed at young ages, probably indicating a recent infection. In older patients EBV was mostly detected in epithelial cells, suggesting that they could have been infected some time ago. This finding was sustained by tonsillar viral load, which was higher in cases with LMP1+SubEp cells vs. LMP1+nonSubEp cells (p = 0.0237, Mann-Whiney test). Latency III was prevalent and related to the GC, while latency II was associated with non-GC (p = 0.0159, χ2 test). EBERs+/IgD+ cells were statistically prevalent over EBERs+/CD27+ cells (p = 0.0021, χ2 test). These findings indicated that both EBV infection models are not mutually exclusive and provide some basis for further understanding of EBV infection dynamics. Moreover, we provide a more accurate explanation of EBV infection in pediatric asymptomatic carriers from a developing country. PMID:26988293

  17. Initiation of DNA Replication within oriP Is Dispensable for Stable Replication of the Latent Epstein-Barr Virus Chromosome after Infection of Established Cell Lines

    PubMed Central

    Norio, Paolo; Schildkraut, Carl L.; Yates, John L.

    2000-01-01

    The 165-kb circularized chromosome of Epstein-Barr virus (EBV) is replicated in latently infected cells once per cell cycle by host proteins during S phase. Replication initiates at multiple sites on latent EBV chromosomes, including within a 1.8-kb region called oriP, which can provide both replication and stabilization for recombinant plasmids in the presence of the EBV-encoded protein, EBNA-1. Replication initiates at or near the dyad symmetry component (DS) of oriP, which depends on multiple EBNA-1 binding sites for activity. To test the importance of the replication function of oriP, the DS was deleted from the viral genome. EBV mutants lacking the DS and carrying a selectable gene could establish latent infections in BL30 cells, in which circular, mutant viral chromosomes were stably maintained. Analysis of replication fork movement using two-dimensional gel electrophoresis showed that the deletion of the DS reduced the initiation events to an undetectable level within the oriP region so that this segment was replicated exclusively by forks entering the region from either direction. A significant slowing or stalling of replication forks that occurs normally at the approximate position of the DS was also eliminated by deletion of the DS. The results confirm the DS as both a replication origin and a place where replication forks pause. Since the replication function of oriP is dispensable at least in certain cell lines, the essential role of EBNA-1 for infection of these cell lines is likely to be that of stabilizing the EBV chromosome by associating with the 30-bp repeats of oriP. The results also imply that in established cell lines, the EBV chromosome can be efficiently replicated entirely from origins that are activated by cellular factors. Presumably, initiation of replication at the DS, mediated by EBNA-1, is important for the natural life cycle of EBV, perhaps in establishing latent infections of normal B cells. PMID:10954558

  18. Microtubule depolymerization activates the Epstein-Barr virus lytic cycle through protein kinase C pathways in nasopharyngeal carcinoma cells.

    PubMed

    Liu, Yi-Ru; Huang, Sheng-Yen; Chen, Jen-Yang; Wang, Lily Hui-Ching

    2013-12-01

    Elevated levels of antibodies against Epstein-Barr virus (EBV) and the presence of viral DNA in plasma are reliable biomarkers for the diagnosis of nasopharyngeal carcinoma (NPC) in high-prevalence areas, such as South-East Asia. The presence of these viral markers in the circulation suggests that a minimal level of virus reactivation may have occurred in an infected individual, although the underlying mechanism of reactivation remains to be elucidated. Here, we showed that treatment with nocodazole, which provokes the depolymerization of microtubules, induces the expression of two EBV lytic cycle proteins, Zta and EA-D, in EBV-positive NPC cells. This effect was independent of mitotic arrest, as viral reactivation was not abolished in cells synchronized at interphase. Notably, the induction of Zta by nocodazole was mediated by transcriptional upregulation via protein kinase C (PKC). Pre-treatment with inhibitors for PKC or its downstream signalling partners p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) abolished the nocodazole-mediated induction of Zta and EA-D. Interestingly, the effect of nocodazole, as well as colchicine and vinblastine, on lytic gene expression occurred only in NPC epithelial cells but not in cells derived from lymphocytes. These results establish a novel role of microtubule integrity in controlling the EBV life cycle through PKC and its downstream pathways, which represents a tissue-specific mechanism for controlling the life-cycle switch of EBV. PMID:24062531

  19. Microtubule depolymerization activates the Epstein-Barr virus lytic cycle through protein kinase C pathways in nasopharyngeal carcinoma cells.

    PubMed

    Liu, Yi-Ru; Huang, Sheng-Yen; Chen, Jen-Yang; Wang, Lily Hui-Ching

    2013-12-01

    Elevated levels of antibodies against Epstein-Barr virus (EBV) and the presence of viral DNA in plasma are reliable biomarkers for the diagnosis of nasopharyngeal carcinoma (NPC) in high-prevalence areas, such as South-East Asia. The presence of these viral markers in the circulation suggests that a minimal level of virus reactivation may have occurred in an infected individual, although the underlying mechanism of reactivation remains to be elucidated. Here, we showed that treatment with nocodazole, which provokes the depolymerization of microtubules, induces the expression of two EBV lytic cycle proteins, Zta and EA-D, in EBV-positive NPC cells. This effect was independent of mitotic arrest, as viral reactivation was not abolished in cells synchronized at interphase. Notably, the induction of Zta by nocodazole was mediated by transcriptional upregulation via protein kinase C (PKC). Pre-treatment with inhibitors for PKC or its downstream signalling partners p38 mitogen-activated protein kinase (MAPK) and c-Jun N-terminal kinase (JNK) abolished the nocodazole-mediated induction of Zta and EA-D. Interestingly, the effect of nocodazole, as well as colchicine and vinblastine, on lytic gene expression occurred only in NPC epithelial cells but not in cells derived from lymphocytes. These results establish a novel role of microtubule integrity in controlling the EBV life cycle through PKC and its downstream pathways, which represents a tissue-specific mechanism for controlling the life-cycle switch of EBV.

  20. Antitumour activity of Bauhinia variegata on Dalton's ascitic lymphoma.

    PubMed

    Rajkapoor, B; Jayakar, B; Murugesh, N

    2003-11-01

    The antitumour activity of the ethanol extract of Bauhinia variegata (EBV) has been evaluated against Dalton's ascitic lymphoma (DAL) in Swiss albino mice. A significant enhancement of mean survival time of EBV-treated tumour bearing mice was found with respect to control group. EBV treatment was found to enhance peritoneal cell counts. After 14 days of inoculation, EBV is able to reverse the changes in the haemotological parameters, protein and PCV consequent to tumour inoculation.

  1. Cell-to-Cell Contact as an Efficient Mode of Epstein-Barr Virus Infection of Diverse Human Epithelial Cells

    PubMed Central

    Imai, Shosuke; Nishikawa, Jun; Takada, Kenzo

    1998-01-01

    We show clear evidence for direct infection of various human epithelial cells by Epstein-Barr virus (EBV) in vitro. The successful infection was achieved by using recombinant EBV (Akata strain) carrying a selective marker gene but without any other artificial operations, such as introduction of the known EBV receptor (CD21) gene or addition of polymeric immunoglobulin A against viral gp350 in culture. Of 21 human epithelial cell lines examined, 18 became infected by EBV, as ascertained by the detection of EBV-determined nuclear antigen (EBNA) 1 expression in the early period after virus exposure, and the following selection culture easily yielded a number of EBV-infected clones from 15 cell lines. None of the human fibroblasts and five nonhuman-derived cell lines examined was susceptible to the infection. By comparison, cocultivation with virus producers showed ≈800-fold-higher efficiency of infection than cell-free infection did, suggesting the significance of direct cell-to-cell contact as a mode of virus spread in vivo. Most of the epithelial cell lines infectable with EBV were negative for CD21 expression at the protein and mRNA levels. The majority of EBV-infected clones established from each cell line invariably expressed EBNA1, EBV-encoded small RNAs, rightward transcripts from the BamHI-A region of the virus genome, and latent membrane protein (LMP) 2A, but not the other EBNAs or LMP1. This restricted form of latent viral gene expression, which is a central issue for understanding epithelial oncogenesis by EBV, resembled that seen in EBV-associated gastric carcinoma and LMP1-negative nasopharyngeal carcinoma. The results indicate that direct infection of epithelial cells by EBV may occur naturally in vivo, and this could be mediated by an unidentified, epithelium-specific binding receptor for EBV. The EBV convertants are viewed, at least in terms of viral gene expression, as in vitro analogs of EBV-associated epithelial tumor cells, thus facilitating

  2. EGFR regulates macrophage activation and function in bacterial infection.

    PubMed

    Hardbower, Dana M; Singh, Kshipra; Asim, Mohammad; Verriere, Thomas G; Olivares-Villagómez, Danyvid; Barry, Daniel P; Allaman, Margaret M; Washington, M Kay; Peek, Richard M; Piazuelo, M Blanca; Wilson, Keith T

    2016-09-01

    EGFR signaling regulates macrophage function, but its role in bacterial infection has not been investigated. Here, we assessed the role of macrophage EGFR signaling during infection with Helicobacter pylori, a bacterial pathogen that causes persistent inflammation and gastric cancer. EGFR was phosphorylated in murine and human macrophages during H. pylori infection. In human gastric tissues, elevated levels of phosphorylated EGFR were observed throughout the histologic cascade from gastritis to carcinoma. Deleting Egfr in myeloid cells attenuated gastritis and increased H. pylori burden in infected mice. EGFR deficiency also led to a global defect in macrophage activation that was associated with decreased cytokine, chemokine, and NO production. We observed similar alterations in macrophage activation and disease phenotype in the Citrobacter rodentium model of murine infectious colitis. Mechanistically, EGFR signaling activated NF-κB and MAPK1/3 pathways to induce cytokine production and macrophage activation. Although deletion of Egfr had no effect on DC function, EGFR-deficient macrophages displayed impaired Th1 and Th17 adaptive immune responses to H. pylori, which contributed to decreased chronic inflammation in infected mice. Together, these results indicate that EGFR signaling is central to macrophage function in response to enteric bacterial pathogens and is a potential therapeutic target for infection-induced inflammation and associated carcinogenesis.

  3. EGFR regulates macrophage activation and function in bacterial infection.

    PubMed

    Hardbower, Dana M; Singh, Kshipra; Asim, Mohammad; Verriere, Thomas G; Olivares-Villagómez, Danyvid; Barry, Daniel P; Allaman, Margaret M; Washington, M Kay; Peek, Richard M; Piazuelo, M Blanca; Wilson, Keith T

    2016-09-01

    EGFR signaling regulates macrophage function, but its role in bacterial infection has not been investigated. Here, we assessed the role of macrophage EGFR signaling during infection with Helicobacter pylori, a bacterial pathogen that causes persistent inflammation and gastric cancer. EGFR was phosphorylated in murine and human macrophages during H. pylori infection. In human gastric tissues, elevated levels of phosphorylated EGFR were observed throughout the histologic cascade from gastritis to carcinoma. Deleting Egfr in myeloid cells attenuated gastritis and increased H. pylori burden in infected mice. EGFR deficiency also led to a global defect in macrophage activation that was associated with decreased cytokine, chemokine, and NO production. We observed similar alterations in macrophage activation and disease phenotype in the Citrobacter rodentium model of murine infectious colitis. Mechanistically, EGFR signaling activated NF-κB and MAPK1/3 pathways to induce cytokine production and macrophage activation. Although deletion of Egfr had no effect on DC function, EGFR-deficient macrophages displayed impaired Th1 and Th17 adaptive immune responses to H. pylori, which contributed to decreased chronic inflammation in infected mice. Together, these results indicate that EGFR signaling is central to macrophage function in response to enteric bacterial pathogens and is a potential therapeutic target for infection-induced inflammation and associated carcinogenesis. PMID:27482886

  4. Schistosoma mansoni, nematode infections, and progression to active tuberculosis among HIV-1-infected Ugandans.

    PubMed

    Brown, Michael; Miiro, George; Nkurunziza, Peter; Watera, Christine; Quigley, Maria A; Dunne, David W; Whitworth, James A G; Elliott, Alison M

    2006-05-01

    Rates of tuberculosis (TB) in Africa are highest among people infected with HIV. Searching for additional risk factors in a cohort of HIV-infected Ugandan adults, we previously found that a type 2 cytokine bias and eosinophilia were associated with progression to active TB. A possible role for helminth infection was assessed in this study. We analyzed TB incidence in 462 members of this cohort who were screened for filarial infections, gastrointestinal nematodes, and schistosomiasis. Progression to TB was not associated with gastrointestinal nematodes (rate ratio [RR], 1.18; confidence intervals [CIs], 0.66-2.10) or Mansonella perstans (RR, 0.42; CI, 0.13-1.34). A weak association between Schistosoma mansoni infection and TB was found (RR, 1.42; CI, 0.86-2.34); after adjusting for potential explanatory variables and using more stringent diagnostic criteria, the association was strengthened (RR, 2.31; 1.00-5.33). This analysis suggests an effect of S. mansoni infection on progression to active TB among HIV-1-infected Ugandans. PMID:16687687

  5. Epstein-Barr Virus-Encoded Latent Membrane Protein 1 Impairs G2 Checkpoint in Human Nasopharyngeal Epithelial Cells through Defective Chk1 Activation

    PubMed Central

    Deng, Wen; Pang, Pei Shin; Tsang, Chi Man; Hau, Pok Man; Yip, Yim Ling; Cheung, Annie L. M.; Tsao, Sai Wah

    2012-01-01

    Nasopharyngeal carcinoma (NPC) is a common cancer in Southeast Asia, particularly in southern regions of China. EBV infection is closely associated with NPC and has long been postulated to play an etiological role in the development of NPC. However, the role of EBV in malignant transformation of nasopharyngeal epithelial cells remains enigmatic. The current hypothesis of NPC development is that premalignant nasopharyngeal epithelial cells harboring genetic alterations support EBV infection and expression of EBV genes induces further genomic instability to facilitate the development of NPC. The latent membrane protein 1 (LMP1) is a well-documented EBV-encoded oncogene. The involvement of LMP1 in human epithelial malignancies has been implicated, but the mechanisms of oncogenic actions of LMP1, particularly in nasopharyngeal cells, are unclear. Here we observed that LMP1 expression in nasopharyngeal epithelial cells impaired G2 checkpoint, leading to formation of unrepaired chromatid breaks in metaphases after γ-ray irradiation. We further found that defective Chk1 activation was involved in the induction of G2 checkpoint defect in LMP1-expressing nasopharyngeal epithelial cells. Impairment of G2 checkpoint could result in loss of the acentrically broken chromatids and propagation of broken centric chromatids in daughter cells exiting mitosis, which facilitates chromosome instability. Our findings suggest that LMP1 expression facilitates genomic instability in cells under genotoxic stress. Elucidation of the mechanisms involved in LMP1-induced genomic instability in nasopharyngeal epithelial cells will shed lights on the understanding of role of EBV infection in NPC development. PMID:22761726

  6. Type I Interferon Elevates Co-Regulatory Receptor Expression on CMV- and EBV-Specific CD8 T Cells in Chronic Hepatitis C

    PubMed Central

    Owusu Sekyere, Solomon; Suneetha, Pothakamuri Venkata; Hardtke, Svenja; Falk, Christine Susanne; Hengst, Julia; Manns, Michael Peter; Cornberg, Markus; Wedemeyer, Heiner; Schlaphoff, Verena

    2015-01-01

    Hepatitis C virus (HCV) readily sets up persistence in a large fraction of infected hosts. Mounting epidemiological and immunological evidence suggest that HCV’s persistence could influence immune responses toward unrelated pathogens and vaccines. Nonetheless, the fundamental contribution of the inflammatory milieu during persistent HCV infection in impacting immune cells specific for common pathogens such as CMV and EBV has not been fully studied. As the co-regulatory receptors PD-1, Tim-3, and 2B4 have all been shown to be vital in regulating CD8+ T cell function, we assessed their expression on CMV/EBV-specific CD8+ T cells from patients with chronic hepatitis C (CHC) and healthy controls ex vivo and upon stimulation with virus-specific peptides in vitro. Total and CMV/EBV-specific CD8+ T cells expressing PD-1, Tim-3, and 2B4 were highly enriched in patients with CHC compared to healthy individuals ex vivo. In vitro peptide stimulation further potentiated the differential co-regulatory receptor expression of PD-1, Tim-3, and 2B4, which then culminated in an enhanced functionality of CMV/EBV-specific CD8+ T cells in CHC patients. Comprehensively analyzing plasma cytokines between the two cohorts, we observed that not only was IFNα-2a dominant among 21 other inflammatory mediators elevated in CHC patients but it also correlated with PD-1 and Tim-3 expressions ex vivo. Importantly, IFNα-2a further caused upregulation of these markers upon in vitro peptide stimulation. Finally, we could prospectively study patients receiving novel IFN-free antiviral therapy. Here, we observed that treatment-induced clearance of HCV resulted in a partial reversion of the phenotype of CMV/EBV-specific CD8+ T cells in patients with CHC. These data reveal an alteration of the plasma concentrations of IFNα-2a together with other inflammatory mediators during CHC, which appeared to pervasively influence co-regulatory receptor expression on CMV/EBV-specific CD8+ T cells. PMID:26113847

  7. Active hepatic capsulitis caused by Paragonimus westermani infection.

    PubMed

    Sasaki, Michiro; Kamiyama, Takuro; Yano, Takeshi; Nakamura-Uchiyama, Fukumi; Nawa, Yukifumi

    2002-08-01

    Paragonimiasis is an important re-emerging parasitosis in Japan. Although the lungs and pleural cavity are the principal sites affected with the parasite, ectopic infection can occur in unexpected sites such as skin and brain. This case report describes a patient with active hepatic capsulitis due to Paragonimus westermani infection. The patient was successfully treated with praziquantel at the dose of 75 mg/kg/day for 3 days.

  8. Immune parameters differentiating active from latent tuberculosis infection in humans.

    PubMed

    Lee, Ji Yeon; Jung, Young Won; Jeong, Ina; Joh, Joon-Sung; Sim, Soo Yeon; Choi, Boram; Jee, Hyeon-Gun; Lim, Dong-Gyun

    2015-12-01

    Tuberculosis remains a highly prevalent infectious disease worldwide. Identification of the immune parameters that differentiate active disease from latent infection will facilitate the development of efficient control measures as well as new diagnostic modalities for tuberculosis. Here, we investigated the cytokine production profiles of monocytes and CD4(+) T lymphocytes upon encountering mycobacterial antigens. In addition, cytokines and lipid mediators with immune-modulating activities were examined in plasma samples ex vivo. Comparison of these parameters in active tuberculosis patients and healthy subjects with latent infection revealed that, active tuberculosis was associated with diminished Th1-type cytokine secretion from CD4(+) T cells and less augmented inflammatory cytokine secretion from monocytes induced by IFN-γ than that in latent tuberculosis infection. In addition, a higher plasma concentration of lipoxin A4 and lower ratio of prostaglandin E2 to lipoxin A4 were observed in active cases than in latent infections. These findings have implications for preparing new therapeutic strategies and for differential diagnosis of the two types of tuberculosis infection.

  9. Antibodies to Lytic Infection Proteins in Lymphocryptovirus-Infected Rhesus Macaques: a Model for Humoral Immune Responses to Epstein-Barr Virus Infection

    PubMed Central

    Orlova, Nina; Fogg, Mark H.; Carville, Angela; Wang, Fred

    2011-01-01

    Humoral immune responses to rhesus lymphocryptovirus (rhLCV) lytic infection proteins were evaluated in the rhesus macaque animal model for Epstein-Barr virus (EBV) infection. We found a hierarchy of humoral responses to 14 rhLCV lytic infection proteins in naturally infected rhesus macaques, with (i) widespread and robust responses to four glycoproteins expressed as late proteins, (ii) frequent but less robust responses to a subset of early proteins, and (iii) low-level responses to immediate-early proteins. This hierarchy of humoral responses was similar to that reported for EBV-infected humans, with the notable exception of the response to rhBARF1. Serum antibodies to rhBARF1 were frequently detected in healthy rhLCV-infected macaques, but in humans, anti-BARF1 antibodies have been reported primarily in patients with EBV-positive nasopharyngeal carcinoma (NPC). The macaque data accurately predicted that serum antibodies against BARF1 are a normal response to EBV infection when human serum samples are analyzed. The rhesus macaque animal provides a unique perspective on humoral responses to EBV infection in humans and can be a valuable model for EBV vaccine development. PMID:21734064

  10. [Identification of Env-specific monoclonal antibodies from Chinese HIV-1 infected person by B cell activation and RT-PCR cloning].

    PubMed

    Wang, Hui-Min; Xu, Ke; Yu, Shuang-Qing; Ding, Lin-Lin; Luo, Hai-Yan; Flinko, Robin; Lewis, George K; Feng, Xia; Shao, Ji-Rong; Guan, Yong-Jun; Zeng, Yi

    2012-06-01

    To obtain protective human monoclonal antibody from HIV-1 infected person, we adapted a technology for isolating antigen specific monoclonal antibody from human memory B cells through in vitro B cell activation coupled with RT-PCT and expression cloning. Human B cells were purified by negative sorting from PBMCs of HIV-1 infected individuals and memory B cells were further enriched using anti-CD27 microbeads. Two hundred memory B cells per well were cultured in 96-well round-bottom plates Env-specific antibodies in supernatants were with feeder cells in medium containing EBV and CpG. screened by ELISA after 1-2 weeks' culture. Cells from positive wells of Env-specific antibody were harvested and total RNA was isolated. Human VH and Vkappa or Vlambda genes were amplified by RT-PCR and cloned into IgG1 and kappa or lambda expressing vectors. Functional VH and Vkappa or Vlambda were identified by cotransfecting 293T cells with individual heavy chain and light chain clones followed by analysis of culture supernatants by ELISA for Env-specific antibodies. Finally, corresponding mAb was produced by transient transfection of 293T cells with the identified VH and Vkappa/lambda pair and purified by protein A affinity chromatography. Purified monocolonal antibodies were used for HIV-1 specific antibody-dependent cell-mediated cytotoxicity (ADCC) and neutralizing activity assay. Four monocolonal Env-specific antibodies were isolated from one HIV-1 subtype B' infected individual. Two of them showed strong ADCC activity and one showed weak neutralizing activity against HIV-1. Its further studies on their application in therapeutic or prophylactic vaccines against HIV-1 should be grounded. PMID:22978159

  11. LL-37 immunomodulatory activity during Mycobacterium tuberculosis infection in macrophages.

    PubMed

    Torres-Juarez, Flor; Cardenas-Vargas, Albertina; Montoya-Rosales, Alejandra; González-Curiel, Irma; Garcia-Hernandez, Mariana H; Enciso-Moreno, Jose A; Hancock, Robert E W; Rivas-Santiago, Bruno

    2015-12-01

    Tuberculosis is one of the most important infectious diseases worldwide. The susceptibility to this disease depends to a great extent on the innate immune response against mycobacteria. Host defense peptides (HDP) are one of the first barriers to counteract infection. Cathelicidin (LL-37) is an HDP that has many immunomodulatory effects besides its weak antimicrobial activity. Despite advances in the study of the innate immune response in tuberculosis, the immunological role of LL-37 during M. tuberculosis infection has not been clarified. Monocyte-derived macrophages were infected with M. tuberculosis strain H37Rv and then treated with 1, 5, or 15 μg/ml of exogenous LL-37 for 4, 8, and 24 h. Exogenous LL-37 decreased tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) while inducing anti-inflammatory IL-10 and transforming growth factor β (TGF-β) production. Interestingly, the decreased production of anti-inflammatory cytokines did not reduce antimycobacterial activity. These results are consistent with the concept that LL-37 can modulate the expression of cytokines during mycobacterial infection and this activity was independent of the P2X7 receptor. Thus, LL-37 modulates the response of macrophages during infection, controlling the expression of proinflammatory and anti-inflammatory cytokines.

  12. LL-37 Immunomodulatory Activity during Mycobacterium tuberculosis Infection in Macrophages

    PubMed Central

    Torres-Juarez, Flor; Cardenas-Vargas, Albertina; Montoya-Rosales, Alejandra; González-Curiel, Irma; Garcia-Hernandez, Mariana H.; Enciso-Moreno, Jose A.; Hancock, Robert E. W.

    2015-01-01

    Tuberculosis is one of the most important infectious diseases worldwide. The susceptibility to this disease depends to a great extent on the innate immune response against mycobacteria. Host defense peptides (HDP) are one of the first barriers to counteract infection. Cathelicidin (LL-37) is an HDP that has many immunomodulatory effects besides its weak antimicrobial activity. Despite advances in the study of the innate immune response in tuberculosis, the immunological role of LL-37 during M. tuberculosis infection has not been clarified. Monocyte-derived macrophages were infected with M. tuberculosis strain H37Rv and then treated with 1, 5, or 15 μg/ml of exogenous LL-37 for 4, 8, and 24 h. Exogenous LL-37 decreased tumor necrosis factor alpha (TNF-α) and interleukin-17 (IL-17) while inducing anti-inflammatory IL-10 and transforming growth factor β (TGF-β) production. Interestingly, the decreased production of anti-inflammatory cytokines did not reduce antimycobacterial activity. These results are consistent with the concept that LL-37 can modulate the expression of cytokines during mycobacterial infection and this activity was independent of the P2X7 receptor. Thus, LL-37 modulates the response of macrophages during infection, controlling the expression of proinflammatory and anti-inflammatory cytokines. PMID:26351280

  13. Toxoplasma gondii Actively Inhibits Neuronal Function in Chronically Infected Mice

    PubMed Central

    Haroon, Fahad; Händel, Ulrike; Angenstein, Frank; Goldschmidt, Jürgen; Kreutzmann, Peter; Lison, Holger; Fischer, Klaus-Dieter; Scheich, Henning; Wetzel, Wolfram; Schlüter, Dirk; Budinger, Eike

    2012-01-01

    Upon infection with the obligate intracellular parasite Toxoplasma gondii, fast replicating tachyzoites infect a broad spectrum of host cells including neurons. Under the pressure of the immune response, tachyzoites convert into slow-replicating bradyzoites, which persist as cysts in neurons. Currently, it is unclear whether T. gondii alters the functional activity of neurons, which may contribute to altered behaviour of T. gondii–infected mice and men. In the present study we demonstrate that upon oral infection with T. gondii cysts, chronically infected BALB/c mice lost over time their natural fear against cat urine which was paralleled by the persistence of the parasite in brain regions affecting behaviour and odor perception. Detailed immunohistochemistry showed that in infected neurons not only parasitic cysts but also the host cell cytoplasm and some axons stained positive for Toxoplasma antigen suggesting that parasitic proteins might directly interfere with neuronal function. In fact, in vitro live cell calcium (Ca2+) imaging studies revealed that tachyzoites actively manipulated Ca2+ signalling upon glutamate stimulation leading either to hyper- or hypo-responsive neurons. Experiments with the endoplasmatic reticulum Ca2+ uptake inhibitor thapsigargin indicate that tachyzoites deplete Ca2+ stores in the endoplasmatic reticulum. Furthermore in vivo studies revealed that the activity-dependent uptake of the potassium analogue thallium was reduced in cyst harbouring neurons indicating their functional impairment. The percentage of non-functional neurons increased over time In conclusion, both bradyzoites and tachyzoites functionally silence infected neurons, which may significantly contribute to the altered behaviour of the host. PMID:22530040

  14. Ultrasonographic Gallbladder Abnormality of Primary Epstein–Barr Virus Infection in Children and Its Influence on Clinical Outcome

    PubMed Central

    Yi, Dae Yong; Kim, Ji Young; Yang, Hye Ran

    2015-01-01

    Abstract The incidence of pediatric acute inflammatory gallbladder (GB) disease without gallstone such as acute acalculous cholecystitis has increased with the development of improved diagnostic modalities. Although Epstein–Barr virus (EBV) infection is common in general population, only few cases of GB diseases caused by EBV infection have been reported. This study analyzed ultrasonographic characteristics of primary EBV infection in children and evaluated the influence of EBV-associated GB disease on clinical course and outcome of EBV infection. Between March 2004 and January 2013, 94 of 287 pediatric patients with EBV infection underwent abdominal ultrasonography (USG); clinical features, laboratory data, and USG findings were collected and analyzed retrospectively. Of 94 children, ultrasonographic thick GB wall was observed in 24 (25.3%). Platelet counts were lower in the thickened GB wall group than in the normal GB wall thickness group (P = 0.004). Direct bilirubin, alanine aminotransferase, and γ-glutamyl transferase levels were higher in the thickened GB wall group (P = 0.000, P = 0.041, and P = 0.001, respectively). The duration of hospitalization was longer in patients with thickened GB wall (P = 0.043). Radiologic findings of acute acalculous inflammatory GB disease such as thickened GB wall caused by primary EBV infection are more common than previously reported. Consideration of EBV infection in the differential diagnosis of children suspected with acute acalculous GB diseases may avoid unnecessary surgical intervention. PMID:26166109

  15. Disseminated rhodococcus equi infection in HIV infection despite highly active antiretroviral therapy

    PubMed Central

    2011-01-01

    Background Rhodococcus equi (R.equi) is an acid fast, GRAM + coccobacillus, which is widespread in the soil and causes pulmonary and extrapulmonary infections in immunocompromised people. In the context of HIV infection, R.equi infection (rhodococcosis) is regarded as an opportunistic disease, and its outcome is influenced by highly active antiretroviral therapy (HAART). Case presentation We report two cases of HIV-related rhodococcosis that disseminated despite suppressive HAART and anti-rhodococcal treatment; in both cases there was no immunological recovery, with CD4+ cells count below 200/μL. In the first case, pulmonary rhodococcosis presented 6 months after initiation of HAART, and was followed by an extracerebral intracranial and a cerebral rhodococcal abscess 1 and 8 months, respectively, after onset of pulmonary infection. The second case was characterized by a protracted course with spread of infection to various organs, including subcutaneous tissue, skin, colon and other intra-abdominal tissues, and central nervous system; the spread started 4 years after clinical resolution of a first pulmonary manifestation and progressed over a period of 2 years. Conclusions Our report highlights the importance of an effective immune recovery, despite fully suppressive HAART, along with anti-rhodococcal therapy, in order to clear rhodococcal infection. PMID:22168333

  16. Cytologic and immunocytochemical features of EBV negative primary effusion lymphoma: report on seven Japanese cases.

    PubMed

    Kishimoto, Koji; Kitamura, Takashi; Hirayama, Yoshiko; Tate, Genshu; Mitsuya, Toshiyuki

    2009-04-01

    Primary effusion lymphoma (PEL) is very rare type of non-Hodgkin's lymphoma (NHL) usually confined to the body cavities such as the pleural space, pericardium, and peritoneum. PEL is a human herpes virus-8 (HHV-8)-associated lymphoma and commonly observed in human immunodeficiency virus (HIV)-infected patients. However, HIV-infected patients are extremely fewer in Japan in comparison with those in Western countries; PEL is usually not associated with HIV infection in Japan. This report presents seven Japanese cases of PEL. In situ hybridization revealed that the PEL cells were negative for EBV in all cases. An immunocytological analysis showed that only one case was positive for HHV-8, and PEL cells were positive for CD20 in all cases. MUM1 was positive, but CD10 and CD138 were negative in six cases. One case each was positive for CD30 and BCL-6. The phenotypic patterns of HIV-related is BCL6-/MUM1+/CD138+, thus, the phenotypic findings observed by immunocytochemistry in this study were somehow different from those reported in Western countries. However, the cytomorphological features of PEL cells showed large cell size, abundant basophilic cytoplasm, coarse chromatin, and occasional binucleated or multinucleated cells, similar to a large cell immunoblastic and anaplastic large cell lymphoma, indicating that the cytomorphological characteristics of PE cells in Giemsa and Papanicolaou stain were consistent with those reported abroad. The prognosis for PEL in these cases was poor, but the survival time was variable ranging from 1 month to 54 months, and was different from that of Western cases. No p16/CDKN2A expression was observed, and one case showed PEL cells with a BLIMP1 mutation.

  17. LAG3 Expression in Active Mycobacterium tuberculosis Infections

    PubMed Central

    Phillips, Bonnie L.; Mehra, Smriti; Ahsan, Muhammad H.; Selman, Moises; Khader, Shabaana A.; Kaushal, Deepak

    2016-01-01

    Mycobacterium tuberculosis (MTB) is a highly successful pathogen because of its ability to persist in human lungs for long periods of time. MTB modulates several aspects of the host immune response. Lymphocyte-activation gene 3 (LAG3) is a protein with a high affinity for the CD4 receptor and is expressed mainly by regulatory T cells with immunomodulatory functions. To understand the function of LAG3 during MTB infection, a nonhuman primate model of tuberculosis, which recapitulates key aspects of natural human infection in rhesus macaques (Macaca mulatta), was used. We show that the expression of LAG3 is highly induced in the lungs and particularly in the granulomatous lesions of macaques experimentally infected with MTB. Furthermore, we show that LAG3 expression is not induced in the lungs and lung granulomas of animals exhibiting latent tuberculosis infection. However, simian immunodeficiency virus–induced reactivation of latent tuberculosis infection results in an increased expression of LAG3 in the lungs. This response is not observed in nonhuman primates infected with non-MTB bacterial pathogens, nor with simian immunodeficiency virus alone. Our data show that LAG3 was expressed primarily on CD4+ T cells, presumably by regulatory T cells but also by natural killer cells. The expression of LAG3 coincides with high bacterial burdens and changes in the host type 1 helper T-cell response. PMID:25549835

  18. LAG3 expression in active Mycobacterium tuberculosis infections.

    PubMed

    Phillips, Bonnie L; Mehra, Smriti; Ahsan, Muhammad H; Selman, Moises; Khader, Shabaana A; Kaushal, Deepak

    2015-03-01

    Mycobacterium tuberculosis (MTB) is a highly successful pathogen because of its ability to persist in human lungs for long periods of time. MTB modulates several aspects of the host immune response. Lymphocyte-activation gene 3 (LAG3) is a protein with a high affinity for the CD4 receptor and is expressed mainly by regulatory T cells with immunomodulatory functions. To understand the function of LAG3 during MTB infection, a nonhuman primate model of tuberculosis, which recapitulates key aspects of natural human infection in rhesus macaques (Macaca mulatta), was used. We show that the expression of LAG3 is highly induced in the lungs and particularly in the granulomatous lesions of macaques experimentally infected with MTB. Furthermore, we show that LAG3 expression is not induced in the lungs and lung granulomas of animals exhibiting latent tuberculosis infection. However, simian immunodeficiency virus-induced reactivation of latent tuberculosis infection results in an increased expression of LAG3 in the lungs. This response is not observed in nonhuman primates infected with non-MTB bacterial pathogens, nor with simian immunodeficiency virus alone. Our data show that LAG3 was expressed primarily on CD4(+) T cells, presumably by regulatory T cells but also by natural killer cells. The expression of LAG3 coincides with high bacterial burdens and changes in the host type 1 helper T-cell response.

  19. Reducing implant-related infections: active release strategies.

    PubMed

    Hetrick, Evan M; Schoenfisch, Mark H

    2006-09-01

    Despite sterilization and aseptic procedures, bacterial infection remains a major impediment to the utility of medical implants including catheters, artificial prosthetics, and subcutaneous sensors. Indwelling devices are responsible for over half of all nosocomial infections, with an estimate of 1 million cases per year (2004) in the United States alone. Device-associated infections are the result of bacterial adhesion and subsequent biofilm formation at the implantation site. Although useful for relieving associated systemic infections, conventional antibiotic therapies remain ineffective against biofilms. Unfortunately, the lack of a suitable treatment often leaves extraction of the contaminated device as the only viable option for eliminating the biofilm. Much research has focused on developing polymers that resist bacterial adhesion for use as medical device coatings. This tutorial review focuses on coatings that release antimicrobial agents (i.e., active release strategies) for reducing the incidence of implant-associated infection. Following a brief introduction to bacteria, biofilms, and infection, the development and study of coatings that slowly release antimicrobial agents such as antibiotics, silver ions, antibodies, and nitric oxide are covered. The success and limitations of these strategies are highlighted.

  20. Activity of a phenolic dibenzylsulfide against New World arenavirus infections

    PubMed Central

    Gowen, Brian B; Jung, Kie-Hoon; Sefing, Eric J; Wong, Min-Hui; Westover, Jonna B; Smee, Donald F

    2013-01-01

    Background Junín virus (JUNV) and several other Clade B New World arenaviruses cause human disease ranging from mild febrile illness to severe viral hemorrhagic fever (HF). These viruses pose a significant threat to national security and safe and effective therapies are limited outside of Argentina, where immune plasma is the standard of care for treating JUNV infection in cases of Argentine HF. Methods An in vitro screen of the Chemtura library identified several compounds with activity against Tacaribe virus (TCRV), a Clade B arenavirus closely related to JUNV. Of these compounds, D746, a phenolic dibenzylsulfide, was further pursued for additional in vitro studies and evaluated in the AG129 mouse TCRV infection model. Results D746 was found to act during an early to intermediate stage of the TCRV replication cycle and micromolar range activity was confirmed by virus yield reduction assays with both TCRV and JUNV. Although intraperitoneal twice daily treatment regimens were found to be highly effective when started 2 hours prior to TCRV challenge in AG129 mice, post-exposure treatment initiated 3 days after infection was not efficacious. Interestingly, despite the pre-exposure treatment success, D746 did not reduce serum or tissue virus titers during the acute infection. Moreover, D746 elicited ascites fluid accumulation in mice during, as well as independent of, infection. Conclusions Our findings suggest that D746 may be altering the host response to TCRV infection in AG129 mice in a way that limits pathogenesis and thereby protects mice from otherwise lethal infection in the absence of measurable reductions in viral burden. PMID:23337126

  1. A Virtual Look at Epstein-Barr Virus Infection: Simulation Mechanism

    PubMed Central

    Shapiro, M.; Duca, K.A; Lee, K.; Delgado-Eckert, E.; Hawkins, J.; Jarrah, A.S.; Laubenbacher, R.; Polys, N.F.; Hadinoto, V.; Thorley-Lawson, D.A.

    2008-01-01

    Epstein-Barr virus (EBV) is an important human pathogen that establishes a lifelong persistent infection and for which no precise animal model exists. In this paper we describe in detail an agent-based model and computer simulation of EBV infection. Agents representing EBV and sets of B and T lymphocytes move and interact on a three-dimensional grid approximating Waldeyer’s ring, together with abstract compartments for lymph and blood. The simulation allows us to explore the development and resolution of virtual infections in a manner not possible in actual human experiments. Specifically, we identify parameters capable of inducing clearance, persistent infection, or death. PMID:18371986

  2. HLA-restricted presentation of WT1 tumor antigen in B-lymphoblastoid cell lines established using a maxi-EBV system.

    PubMed

    Kanda, T; Ochi, T; Fujiwara, H; Yasukawa, M; Okamoto, S; Mineno, J; Kuzushima, K; Tsurumi, T

    2012-08-01

    Lymphoblastoid cell lines (LCLs), which are established by in vitro infection of peripheral B-lymphocytes with Epstein-Barr virus (EBV), are effective antigen-presenting cells. However, the ability of LCLs to present transduced tumor antigens has not yet been evaluated in detail. We report a single-step strategy utilizing a recombinant EBV (maxi-EBV) to convert B-lymphocytes from any individuals into indefinitely growing LCLs expressing a transgene of interest. The strategy was successfully used to establish LCLs expressing Wilms' tumor gene 1 (WT1) tumor antigen (WT1-LCLs), which is an attractive target for cancer immunotherapy. The established WT1-LCLs expressed more abundant WT1 protein than K562 leukemic cells, which are known to overexpress WT1. A WT1-specific cytotoxic T lymphocyte line efficiently lysed the WT1-LCL in a human leukocyte antigen-restricted manner, but poorly lysed control LCL not expressing WT1. These results indicate that the transduced WT1 antigen is processed and presented on the WT1-LCL. This experimental strategy can be applied to establish LCLs expressing other tumor antigens and will find a broad range of applications in the field of cancer immunotherapy.

  3. Changing patterns in the Epstein-Barr virus (EBV)and Hodgkin lymphoma association in Tunisia.

    PubMed

    Dhiab, Myriam Ben; Ziadi, Sonia; Saad, Hanene; Louhichi, Teheni; Trimeche, Mounir

    2016-09-01

    We compared the features of the Epstein-Barr virus (EBV) and Hodgkin lymphoma (HL) association in Tunisia in two periods of time, 1991-2001 (111 cases) and 2002-2012 (122 cases). The investigation of the EBV status by EBER in situ hybridization showed a significant decrease in the prevalence of EBV-positive HL from 69.3 % for the period 1991-2001 to 40.1 % for the 2002-2012 period (p = 0.00001). EBV positivity has decreased in all age groups but was more pronounced among young patients, in the 15-24-year age group (46.1 vs 10.3 %, p = 0.003), in the 25-34-year age group (56.2 vs 25 %, p = 0.04), and among children (88.4 vs 59.2 %, p = 0.01). This decrease in EBV-positive HL over time contrasted with a remarkable increase in EBV-negative HL in young adults aged 15-34 years (51.2 vs 83 %; p = 0.001), especially among women (59.1 vs 91.2 %; p = 0.01). The decrease in EBV-positive HL over time concerns particularly the nodular sclerosis histological subtype (69.2 vs 31.6 %, p = 0.000001). These results indicate that the epidemiology of HL and its association with EBV are changing over time, with a trend toward a Western profile, and point toward the emergence of other environmental causative factors, especially among young women, which remain to be identified. PMID:27378019

  4. EBV-associated lymphoepithelioma-like carcinoma of the pancreas: case report with targeted sequencing analysis

    PubMed Central

    Samdani, Rashmi T.; Hechtman, Jaclyn F.; O'Reilly, Eileen; DeMatteo, Ronald; Sigel, Carlie S.

    2016-01-01

    Lymphoepithelioma-like carcinomas are distinctive epithelial derived malignant neoplasms that have a syncytial growth pattern and lymphoid stroma. The majority of tumors with this appearance are Epstein Barr virus (EBV)-associated. We report a patient with a clinical presentation concerning for lymphoma who was diagnosed with an EBV-associated pancreatic carcinoma with a lymphoepithelioma-like pattern. Targeted sequencing analysis showed a molecular profile distinct from conventional ductal adenocarcinoma of the pancreas. PMID:25922198

  5. Activated mouse eosinophils protect against lethal respiratory virus infection

    PubMed Central

    Percopo, Caroline M.; Dyer, Kimberly D.; Ochkur, Sergei I.; Luo, Janice L.; Fischer, Elizabeth R.; Lee, James J.; Lee, Nancy A.; Domachowske, Joseph B.

    2014-01-01

    Eosinophils are recruited to the airways as a prominent feature of the asthmatic inflammatory response where they are broadly perceived as promoting pathophysiology. Respiratory virus infections exacerbate established asthma; however, the role of eosinophils and the nature of their interactions with respiratory viruses remain uncertain. To explore these questions, we established acute infection with the rodent pneumovirus, pneumonia virus of mice (PVM), in 3 distinct mouse models of Th2 cytokine–driven asthmatic inflammation. We found that eosinophils recruited to the airways of otherwise naïve mice in response to Aspergillus fumigatus, but not ovalbumin sensitization and challenge, are activated by and degranulate specifically in response to PVM infection. Furthermore, we demonstrate that activated eosinophils from both Aspergillus antigen and cytokine-driven asthma models are profoundly antiviral and promote survival in response to an otherwise lethal PVM infection. Thus, although activated eosinophils within a Th2-polarized inflammatory response may have pathophysiologic features, they are also efficient and effective mediators of antiviral host defense. PMID:24297871

  6. Virus and Autoantigen-Specific CD4+ T Cells Are Key Effectors in a SCID Mouse Model of EBV-Associated Post-Transplant Lymphoproliferative Disorders

    PubMed Central

    Linnerbauer, Stefanie; Behrends, Uta; Adhikary, Dinesh; Witter, Klaus; Bornkamm, Georg W.; Mautner, Josef

    2014-01-01

    Polyclonal Epstein-Barr virus (EBV)-infected B cell line (lymphoblastoid cell lines; LCL)-stimulated T-cell preparations have been successfully used to treat EBV-positive post-transplant lymphoproliferative disorders (PTLD) in transplant recipients, but function and specificity of the CD4+ component are still poorly defined. Here, we assessed the tumor-protective potential of different CD4+ T-cell specificities in a PTLD-SCID mouse model. Injection of different virus-specific CD4+ T-cell clones showed that single specificities were capable of prolonging mouse survival and that the degree of tumor protection directly correlated with recognition of target cells in vitro. Surprisingly, some CD4+ T-cell clones promoted tumor development, suggesting that besides antigen recognition, still elusive functional differences exist among virus-specific T cells. Of several EBV-specific CD4+ T-cell clones tested, those directed against virion antigens proved most tumor-protective. However, enriching these specificities in LCL-stimulated preparations conferred no additional survival benefit. Instead, CD4+ T cells specific for unknown, probably self-antigens were identified as principal antitumoral effectors in LCL-stimulated T-cell lines. These results indicate that virion and still unidentified cellular antigens are crucial targets of the CD4+ T-cell response in this preclinical PTLD-model and that enriching the corresponding T-cell specificities in therapeutic preparations may enhance their clinical efficacy. Moreover, the expression in several EBV-negative B-cell lymphoma cell lines implies that these putative autoantigen(s) might also qualify as targets for T-cell-based immunotherapy of virus-negative B cell malignancies. PMID:24853673

  7. Secreted Oral Epithelial Cell Membrane Vesicles Induce Epstein-Barr Virus Reactivation in Latently Infected B Cells

    PubMed Central

    Lin, Zhen; Swan, Kenneth; Zhang, Xin; Cao, Subing; Brett, Zoe; Drury, Stacy; Fewell, Claire; Puetter, Adriane; Wang, Xia; Ferris, MaryBeth; Sullivan, Deborah E.; Li, Li

    2016-01-01

    ABSTRACT In the oral epithelium, peripheral stores of Epstein-Barr virus (EBV) are transmitted from infiltrating B cells to epithelial cells. Once the virus is transmitted to epithelial cells, the highly permissive nature of this cell type for lytic replication allows virus amplification and exchange to other hosts. Since the initial transfer of EBV from B cells to epithelial cells requires transitioning of the B-cell to a state that induces virus reactivation, we hypothesized that there might be epithelium-specific signals that allow the infiltrating B cells to sense the appropriate environment to initiate reactivation and begin this exchange process. We previously found that the epithelium-specific miR-200 family of microRNAs promotes EBV lytic replication. Here we show that there are high levels of miR-200 family members in oral and tonsillar epithelia and in saliva. Analysis of cultured oral epithelial cells (OKF6) showed that they actively secrete membrane vesicles (exosomes) that are enriched with miR-200 family members. Coculturing of EBV-positive B cells with OKF6 cells induced viral reactivation. Further, treatment of EBV-positive B cells with OKF6 cell-derived membrane vesicles promoted reactivation. Using a cell system that does not naturally express miR-200 family members, we found that enforced expression of a miR-200 family member produced membrane vesicles that were able to induce the lytic cascade in EBV-positive B cells. We propose that membrane vesicles secreted by oral and tonsillar epithelial cells may serve as a tissue-specific environmental cue that initiates reactivation in B cells, promoting the transfer of virus from peripheral B-cell stores to the oral epithelium to facilitate virus amplification and exchange to other hosts. IMPORTANCE Epstein-Barr virus (EBV) is an important human pathogen that is causally associated with several lymphomas and carcinomas. The switch from latency to the lytic cycle is critical for successful host infection

  8. Marine Peptides and Their Anti-Infective Activities

    PubMed Central

    Kang, Hee Kyoung; Seo, Chang Ho; Park, Yoonkyung

    2015-01-01

    Marine bioresources are a valuable source of bioactive compounds with industrial and nutraceutical potential. Numerous clinical trials evaluating novel chemotherapeutic agents derived from marine sources have revealed novel mechanisms of action. Recently, marine-derived bioactive peptides have attracted attention owing to their numerous beneficial effects. Moreover, several studies have reported that marine peptides exhibit various anti-infective activities, such as antimicrobial, antifungal, antimalarial, antiprotozoal, anti-tuberculosis, and antiviral activities. In the last several decades, studies of marine plants, animals, and microbes have revealed tremendous number of structurally diverse and bioactive secondary metabolites. However, the treatments available for many infectious diseases caused by bacteria, fungi, and viruses are limited. Thus, the identification of novel antimicrobial peptides should be continued, and all possible strategies should be explored. In this review, we will present the structures and anti-infective activity of peptides isolated from marine sources (sponges, algae, bacteria, fungi and fish) from 2006 to the present. PMID:25603351

  9. Promiscuous trans activation of gene expression by an Epstein-Barr virus-encoded early nuclear protein.

    PubMed Central

    Lieberman, P M; O'Hare, P; Hayward, G S; Hayward, S D

    1986-01-01

    We identified an Epstein-Barr virus (EBV) gene product which functions in transient-expression assays as a nonspecific trans activator. In Vero cells, cotransfection of the BglII J DNA fragment of EBV together with recombinant constructs containing the bacterial chloramphenicol acetyltransferase (CAT) gene gave up to a 100-fold increased expression of CAT activity over that in cells transfected with the recombinant CAT constructs alone. The BglII J fragment acted promiscuously, in that increased CAT synthesis was observed regardless of whether the promoter sequences driving the CAT gene were of EBV, simian virus 40, adenovirus, or herpes simplex virus origin. Cleavage of cloned BglII-J plasmid DNA before transfection revealed that activation was dependent upon the presence of an intact BMLF1 open reading frame. This was confirmed with subclones of BglII-J and with hybrid promoter-open reading frame constructs. This region of the genome is also present in the rearranged P3HR-1-defective DNA species, and defective DNA clones containing these sequences produced a similar activation of CAT expression in cotransfection experiments. The heterogeneous 45-60-kilodalton polypeptide product of BMLF1 may play an important regulatory role in expression of lytic-cycle proteins in EBV-infected lymphocytes. Images PMID:3018281

  10. Common variable immune deficiency associated Hodgkin’s lymphoma complicated with EBV-linked hemophagocytic lymphohistiocytosis: a case report

    PubMed Central

    Malkan, Umit Yavuz; Gunes, Gursel; Aslan, Tuncay; Etgul, Sezgin; Aydin, Seda; Buyukasik, Yahya

    2015-01-01

    Hemophagocytic syndrome (HPS) is described by an increase in macrophages accountable for extensive phagocytosis of hematopoietic cells. Secondary HPS arises commonly in the presence of infections, neoplasia, autoimmune disorders and immune disorders. Here, we reported a patient with common variable immune deficiency (CVID) and Hodgkin’s lymphoma (HL) who later developed EBV linked hemophagocytic lymphohistiocytosis. 42 year old men underwent check-up because of back pain in July 2012. He had known CVID disease. In physical examination he had no lymphadenopathies however his spleen was palpable 3 cm under arcus costa. He had hypogammaglobulinemia with IgG levels around 500 mg/dl. In abdominal computed tomography (CT) multiple lymphadenopathies reaching maximum 26×17 cm size were seen so, PET-CT was performed. Involvement in thorax, abdomen, and bone was detected with maximum SUV max 11.5. He had undergone tru-cut biopsy from lymph node in November 2012 which revealed HL. Bone marrow investigation favored with mix cell type. His cytogenetic analysis was reported as 46 XY. He was considered as stage 4 disease and ABVD (Adriamycin, bleomycin, vincristine and dexamethasone). He was given six cycles of chemotherapy in May 2013 and complete remission was observed in control CT screening in July 2013. However pancytopenia evolved in August 2013. Bone marrow investigation revealed suspicious lymphohistiocytic infiltration. Treatment was planned to apply autologous stem cell transplantation (SCT) after salvage chemotherapy. Control bone marrow investigation again revealed the lymphohistiocytic aggregates with hemophagocytosis. Our patient showed 5 criteria of hemophagocytic syndrome. He had ferritin elevation (>5000 μg/dl), splenomegaly (13 cm) cytopenia, triglyceride elevation and hemophagocytosis. He had unrelated SCT transplantation however he died from transplant related toxicity. The primary and secondary immune deficiency caused by chemotherapy are the major causes

  11. Effects of atrazine on cercarial longevity, activity, and infectivity.

    PubMed

    Koprivnikar, Janet; Forbes, Mark R; Baker, Robert L

    2006-04-01

    Susceptibility of free-living infective stages of parasites to contaminants is relatively understudied compared with independent effects on measures of host health or immunity, but may be important in affecting prevalence and intensity of parasite infections. We investigated whether atrazine, an herbicide commonly used in North America, affected the cercariae of 4 different species of digenetic trematodes, and found that effects of atrazine concentration on mortality and activity of cercariae varied among species. Mortality of Echinostoma trivolvis increased in a 200 microg/L atrazine solution, and a species of Alaria showed both decreased activity and increased mortality. We also examined whether the ability of E. trivolvis to infect the second intermediate host, larval amphibians, was compromised by atrazine exposure. Longevity and prevalence of E. trivolvis cercariae was affected at 200 microg/L atrazine, whereas intensity of infection in Rana clamitans tadpoles was reduced at both 20 microg/L and 200 microg/L atrazine. Our results indicate that the viability of cercariae of some species is compromised by exposure to atrazine, emphasizing the importance of considering the influence of contaminants on free-living stages of parasites in addressing how environmental degradation may relate to host parasitism.

  12. [Epstein-Barr, hepatitis B and hepatitis C virus infections and their oncogenic potentials].

    PubMed

    Jovanović, J; Brkić, S; Klasnja, B; Fabri, M

    1997-01-01

    There are two ways of connecting Epstein-Barr virus (EBV) with the uncontrolled growth of EBV infected B lymphocytes: in case of evident immunosuppression when the control by cellular immunity is missing or in the case of pathological growth of malignant clone as a result of genetic translocations. Today, EBV is linked with the development of lymphomas in immunosuppressed patients, Hodgkin's and Burkitt's lymphoma and nasopharyngeal carcinoma. The presence of EBV genome in these patients can be confirmed in malignant cells, in lower or higher percent, as well as the high titers of antibodies against specific virus antigens. Hepatitis B viral infection (HBVI) of specific chronic course and associated with intensified inflammation and mitotic activity is of one of the most important factors in the appearance of hepatocellular carcinoma. Although the integration of viral DNA in DNA of hepatocytes has been one of the possible preconditions for carcinogenesis, recently a great attention has been paid to the inactivation of p53 suppressor gene, being a transcriptive transactivator. Other possible cofactors of carcinogenesis imply long-lasting viral replication, coinfection with HVB, HCV or HDV, interaction with other chemical carcinogens (hormones, aflatoxin, alcohol and similar). In distinction from other human DNA viruses, Hepatitis C virus (HCV) is a RNA virus which is not integrated in genome of hepatocyte and active replication of virus is maintained even when hepatocellular carcinoma is detected. It has been assumed that HCV inactivate or mutate the gene of tumor suppression p53 in an early stage of hepatocellular carcinoma development. PMID:9471511

  13. Gelsolin activity controls efficient early HIV-1 infection

    PubMed Central

    2013-01-01

    Background HIV-1 entry into target lymphocytes requires the activity of actin adaptors that stabilize and reorganize cortical F-actin, like moesin and filamin-A. These alterations are necessary for the redistribution of CD4-CXCR4/CCR5 to one pole of the cell, a process that increases the probability of HIV-1 Envelope (Env)-CD4/co-receptor interactions and that generates the tension at the plasma membrane necessary to potentiate fusion pore formation, thereby favouring early HIV-1 infection. However, it remains unclear whether the dynamic processing of F-actin and the amount of cortical actin available during the initial virus-cell contact are required to such events. Results Here we show that gelsolin restructures cortical F-actin during HIV-1 Env-gp120-mediated signalling, without affecting cell-surface expression of receptors or viral co-receptor signalling. Remarkably, efficient HIV-1 Env-mediated membrane fusion and infection of permissive lymphocytes were impaired when gelsolin was either overexpressed or silenced, which led to a loss or gain of cortical actin, respectively. Indeed, HIV-1 Env-gp120-induced F-actin reorganization and viral receptor capping were impaired under these experimental conditions. Moreover, gelsolin knockdown promoted HIV-1 Env-gp120-mediated aberrant pseudopodia formation. These perturbed-actin events are responsible for the inhibition of early HIV-1 infection. Conclusions For the first time we provide evidence that through its severing of cortical actin, and by controlling the amount of actin available for reorganization during HIV-1 Env-mediated viral fusion, entry and infection, gelsolin can constitute a barrier that restricts HIV-1 infection of CD4+ lymphocytes in a pre-fusion step. These findings provide important insights into the complex molecular and actin-associated dynamics events that underlie early viral infection. Thus, we propose that gelsolin is a new factor that can limit HIV-1 infection acting at a pre-fusion step

  14. Adenovirus-Based Vaccines against Rhesus Lymphocryptovirus EBNA-1 Induce Expansion of Specific CD8+ and CD4+ T Cells in Persistently Infected Rhesus Macaques

    PubMed Central

    Leskowitz, R.; Fogg, M. H.; Zhou, X. Y.; Kaur, A.; Silveira, E. L. V.; Villinger, F.; Lieberman, P. M.; Wang, F.

    2014-01-01

    ABSTRACT The impact of Epstein-Barr virus (EBV) on human health is substantial, but vaccines that prevent primary EBV infections or treat EBV-associated diseases are not yet available. The Epstein-Barr nuclear antigen 1 (EBNA-1) is an important target for vaccination because it is the only protein expressed in all EBV-associated malignancies. We have designed and tested two therapeutic EBV vaccines that target the rhesus (rh) lymphocryptovirus (LCV) EBNA-1 to determine if ongoing T cell responses during persistent rhLCV infection in rhesus macaques can be expanded upon vaccination. Vaccines were based on two serotypes of E1-deleted simian adenovirus and were administered in a prime-boost regimen. To further modulate the response, rhEBNA-1 was fused to herpes simplex virus glycoprotein D (HSV-gD), which acts to block an inhibitory signaling pathway during T cell activation. We found that vaccines expressing rhEBNA-1 with or without functional HSV-gD led to expansion of rhEBNA-1-specific CD8+ and CD4+ T cells in 33% and 83% of the vaccinated animals, respectively. Additional animals developed significant changes within T cell subsets without changes in total numbers. Vaccination did not increase T cell responses to rhBZLF-1, an immediate early lytic phase antigen of rhLCV, thus indicating that increases of rhEBNA-1-specific responses were a direct result of vaccination. Vaccine-induced rhEBNA-1-specific T cells were highly functional and produced various combinations of cytokines as well as the cytolytic molecule granzyme B. These results serve as an important proof of principle that functional EBNA-1-specific T cells can be expanded by vaccination. IMPORTANCE EBV is a common human pathogen that establishes a persistent infection through latency in B cells, where it occasionally reactivates. EBV infection is typically benign and is well controlled by the host adaptive immune system; however, it is considered carcinogenic due to its strong association with lymphoid

  15. Aberrant Epstein–Barr viral infection in systemic lupus erythematosus☆

    PubMed Central

    Poole, Brian D.; Templeton, Amanda K.; Guthridge, Joel M.; Brown, Eric J.; Harley, John B.; James, Judith A.

    2010-01-01

    Serologic association, cross-reactivity of select EBV-specific antibodies with SLE autoantigens, SLE-like autoimmunity after immunization with EBV peptides, increased EB viral load in SLE patients, and SLE-specific alterations in EBV humoral and cellular immunity implicate Epstein–Barr virus (EBV) in the development of systemic lupus erythematosus (SLE). To investigate SLE-specific differences in EBV gene expression, levels of eight EBV genes were compared between SLE patients and controls by using both ex vivo-infected and un-manipulated peripheral blood mononuclear cells (PBMCs). Expression levels of mRNA were significantly greater by Wilcoxen signed rank test in the ex vivo-infected SLE patient-derived cells for 4 of 8 EBV genes, including BLLF1, 3.2-fold (p<0.004); LMP-2, 1.7-fold (p<0.008); EBNA-1, 1.7-fold (p<0.01); and BcRF1, a proposed DNA binding protein, 1.7-fold (p<0.02). The frequency of LMP-1 gene expression was significantly greater by Chi square analysis in the peripheral blood from SLE patients than controls (44% of patients, 10% of controls p<0.05). PBMCs from SLE patients had greater expression of latent genes as well as increased expression of both latent and lytic genes after infection, suggesting that EBV may participate in SLE etiology through several mechanisms. Such altered infection patterns may contribute to the increased levels of EBV and the molecular mimicry seen in sera from SLE patients. PMID:19167523

  16. Macrophage Activation by Ursolic and Oleanolic Acids during Mycobacterial Infection.

    PubMed

    López-García, Sonia; Castañeda-Sanchez, Jorge Ismael; Jiménez-Arellanes, Adelina; Domínguez-López, Lilia; Castro-Mussot, Maria Eugenia; Hernández-Sanchéz, Javier; Luna-Herrera, Julieta

    2015-08-06

    Oleanolic (OA) and ursolic acids (UA) are triterpenes that are abundant in vegetables, fruits and medicinal plants. They have been described as active moieties in medicinal plants used for the treatment of tuberculosis. In this study, we analyzed the effects of these triterpenes on macrophages infected in vitro with Mycobacterium tuberculosis (MTB). We evaluated production of nitric oxide (NO), reactive oxygen species (ROS), and cytokines (TNF-α and TGF-β) as well as expression of cell membrane receptors (TGR5 and CD36) in MTB-infected macrophages following treatment with OA and UA. Triterpenes caused reduced MTB growth in macrophages, stimulated production of NO and ROS in the early phase, stimulated TNF-α, suppressed TGF-β and caused over-expression of CD36 and TGR5 receptors. Thus, our data suggest immunomodulatory properties of OA and UA on MTB infected macrophages. In conclusion, antimycobacterial effects induced by these triterpenes may be attributable to the conversion of macrophages from stage M2 (alternatively activated) to M1 (classically activated).

  17. Localised mitogenic activity in horses following infection with Streptococcus equi.

    PubMed

    McLean, R; Rash, N L; Robinson, C; Waller, A S; Paillot, R

    2015-06-01

    Streptococcus equi subspecies equi (S. equi) is the causative agent of strangles, a highly contagious upper respiratory disease of equids. Streptococcus equi produces superantigens (sAgs), which are thought to contribute to strangles pathogenicity through non-specific T-cell activation and pro-inflammatory response. Streptococcus equi infection induces abscesses in the lymph nodes of the head and neck. In some individuals, some abscess material remains into the guttural pouch and inspissates over time to form chondroids which can harbour live S. equi. The aim of this study was to determine the sites of sAg production during infection and therefore improve our understanding of their role. Abscess material, chondroids and serum collected from Equidae with signs of strangles were tested in mitogenic assays. Mitogenic sAg activity was only detected in abscess material and chondroids. Our data support the localised in vivo activity of sAg during both acute and carrier phases of S. equi infection.

  18. Macrophage Activation by Ursolic and Oleanolic Acids during Mycobacterial Infection.

    PubMed

    López-García, Sonia; Castañeda-Sanchez, Jorge Ismael; Jiménez-Arellanes, Adelina; Domínguez-López, Lilia; Castro-Mussot, Maria Eugenia; Hernández-Sanchéz, Javier; Luna-Herrera, Julieta

    2015-01-01

    Oleanolic (OA) and ursolic acids (UA) are triterpenes that are abundant in vegetables, fruits and medicinal plants. They have been described as active moieties in medicinal plants used for the treatment of tuberculosis. In this study, we analyzed the effects of these triterpenes on macrophages infected in vitro with Mycobacterium tuberculosis (MTB). We evaluated production of nitric oxide (NO), reactive oxygen species (ROS), and cytokines (TNF-α and TGF-β) as well as expression of cell membrane receptors (TGR5 and CD36) in MTB-infected macrophages following treatment with OA and UA. Triterpenes caused reduced MTB growth in macrophages, stimulated production of NO and ROS in the early phase, stimulated TNF-α, suppressed TGF-β and caused over-expression of CD36 and TGR5 receptors. Thus, our data suggest immunomodulatory properties of OA and UA on MTB infected macrophages. In conclusion, antimycobacterial effects induced by these triterpenes may be attributable to the conversion of macrophages from stage M2 (alternatively activated) to M1 (classically activated). PMID:26287131

  19. 2-Octynoic Acid Inhibits Hepatitis C Virus Infection through Activation of AMP-Activated Protein Kinase

    PubMed Central

    Yang, Darong; Xue, Binbin; Wang, Xiaohong; Yu, Xiaoyan; Liu, Nianli; Gao, Yimin; Liu, Chen; Zhu, Haizhen

    2013-01-01

    Many chronic hepatitis C virus (HCV)-infected patients with current therapy do not clear the virus. It is necessary to find novel treatments. The effect of 2-octynoic acid (2-OA) on HCV infection in human hepatocytes was examined. The mechanism of 2-OA antiviral activity was explored. Our data showed that 2-OA abrogated lipid accumulation in HCV replicon cells and virus-infected hepatocytes. It suppressed HCV RNA replication and infectious virus production with no cytotoxicity to the host cells. 2-OA did not affect hepatitis B virus replication in HepG2.2.15 cells derived from HepG2 cells transfected with full genome of HBV. Further study demonstrated that 2-OA activated AMP-activated protein kinase (AMPK) and inhibited acetyl-CoA carboxylase in viral-infected cells. Compound C, a specific inhibitor of AMPK, inhibited AMPK activity and reversed the reduction of intracellular lipid accumulation and the antiviral effect of 2-OA. Knockdown of AMPK expression by RNA interference abolished the activation of AMPK by 2-OA and blocked 2-OA antiviral activity. Interestingly, 2-OA induced interferon-stimulated genes (ISGs) and inhibited microRNA-122 (miR-122) expression in virus-infected hepatocytes. MiR-122 overexpression reversed the antiviral effect of 2-OA. Furthermore, knockdown of AMPK expression reversed both the induction of ISGs and suppression of miR-122 by 2-OA, implying that activated AMPK induces the intracellular innate response through the induction of ISGs and inhibiting miR-122 expression. 2-OA inhibits HCV infection through regulation of innate immune response by activated AMPK. These findings reveal a novel mechanism by which active AMPK inhibits HCV infection. 2-OA and its derivatives hold promise for novel drug development for chronic hepatitis C. PMID:23741428

  20. A recombinant modified vaccinia Ankara vaccine encoding Epstein-Barr virus (EBV) target antigens: a phase I trial in UK patients with EBV-positive cancer

    PubMed Central

    Taylor, Graham S.; Jia, Hui; Harrington, Kevin; Lee, Lip Wai; Turner, James; Ladell, Kristin; Price, David A; Tanday, Manjit; Matthews, Jen; Roberts, Claudia; Edwards, Ceri; McGuigan, Lesley; Hartley, Andrew; Wilson, Steve; Hui, Edwin P.; Chan, Anthony T. C.; Rickinson, Alan B.; Steven, Neil M.

    2015-01-01

    Purpose Epstein-Barr virus (EBV) is associated with several cancers in which the tumour cells express EBV antigens EBNA1 and LMP2. A therapeutic vaccine comprising a recombinant vaccinia virus, MVA-EL, was designed to boost immunity to these tumour antigens. A phase I trial was conducted to demonstrate the safety and immunogenicity of MVA-EL across a range of doses. Experimental Design Sixteen patients in the United Kingdom (UK) with EBV-positive nasopharyngeal carcinoma (NPC), received three intradermal vaccinations of MVA-EL at 3-weekly intervals at dose levels between 5×107 and 5×108 plaque forming units (pfu). Blood samples were taken at screening, after each vaccine cycle and during the post-vaccination period. T-cell responses were measured using IFNγ ELISpot assays with overlapping EBNA1/LMP2 peptide mixes or HLA-matched epitope peptides. Polychromatic flow cytometry was used to characterize functionally responsive T-cell populations. Results Vaccination was generally well-tolerated. Immunity increased after vaccination to at least one antigen in 8/14 patients (7/14, EBNA1; 6/14, LMP2), including recognition of epitopes that vary between EBV strains associated with different ethnic groups. Immunophenotypic analysis revealed that vaccination induced differentiation and functional diversification of responsive T-cell populations specific for EBNA1 and LMP2 within the CD4 and CD8 compartments respectively. Conclusions MVA-EL is safe and immunogenic across diverse ethnicities and thus suitable for use in trials against different EBV-positive cancers globally as well as in South East Asia where NPC is most common. The highest dose (5×108 pfu) is recommended for investigation in current phase IB and II trials. PMID:25124688

  1. Characterization of cytomegalovirus and epstein-barr virus infection in cervical lesions in Portugal.

    PubMed

    Marinho-Dias, Joana; Ribeiro, Joana; Monteiro, Paula; Loureiro, Joana; Baldaque, Inês; Medeiros, Rui; Sousa, Hugo

    2013-08-01

    Infection by high-risk types of human papillomavirus (HPV) is considered necessary but not sufficient for the development of cervical cancer. Previous studies suggested that cytomegalovirus (CMV) and Epstein-barr virus (EBV) could be co-factors of HPV-associated carcinogenesis. The aim of this study was to characterize the prevalence of CMV and EBV and evaluate its association with the development cervical lesions in Portugal. The prevalence of CMV and EBV infections was determined by real-time PCR in 89 cervical samples from women with different histological lesions, who attended the Portuguese Institute of Oncology of Porto. This study revealed an overall prevalence of 4.5% for CMV and 10.1% for EBV. Age-stratified analysis revealed that CMV infection was present in individuals <30 and >60 years old, while EBV infection was present in all age groups. CMV was detected in 9.5% of low-grade lesions and in 22.2% of in situ/invasive carcinomas, while EBV infection was found in all different types of lesions. In addition, data revealed that CMV infection was associated with an increased risk of in situ/invasive carcinoma development (OR=1.28; P=0.035). The study reveals a low prevalence for both viruses; nevertheless, these results are important for knowledge on the shedding of EBV and CMV in cervical samples.

  2. Epstein-Barr virus-encoded small RNAs (EBERs) do not modulate interferon effects in infected lymphocytes.

    PubMed Central

    Swaminathan, S; Huneycutt, B S; Reiss, C S; Kieff, E

    1992-01-01

    The recent derivation of otherwise isogenic Epstein-Barr virus (EBV) recombinants carrying or lacking the EBV small RNA (EBER) genes enabled us to test whether EBERs are similar to adenovirus VA RNAs in modulating interferon (IFN) effects on virus infection. EBER-positive and -negative EBV recombinants did not differ in their sensitivity to alpha interferon (IFN-alpha)- or IFN-gamma-mediated inhibition of lymphocyte growth transformation. In addition, EBERs did not decrease the inhibitory effects of IFN on vesicular stomatitis virus replication in EBV-transformed lymphocytes. EBER deletion also did not render EBV-transformed B lymphocytes susceptible to an IFN effect on cell proliferation or EBV replication. Images PMID:1321292

  3. PML nuclear bodies and SATB1 are associated with HLA class I expression in EBV+ Hodgkin lymphoma.

    PubMed

    Liu, Yuxuan; van den Berg, Anke; Veenstra, Rianne; Rutgers, Bea; Nolte, Ilja; van Imhoff, Gustaaf; Visser, Lydia; Diepstra, Arjan

    2013-01-01

    Tumor cells of classical Hodgkin lymphoma (cHL) are characterized by a general loss of B cell phenotype, whereas antigen presenting properties are commonly retained. HLA class I is expressed in most EBV+ cHL cases, with an even enhanced expression in a proportion of the cases. Promyelocytic leukemia protein (PML) and special AT-rich region binding protein 1 (SATB1) are two global chromatin organizing proteins that have been shown to regulate HLA class I expression in Jurkat cells. We analyzed HLA class I, number of PML nuclear bodies (NBs) and SATB1 expression in tumor cells of 54 EBV+ cHL cases and used 27 EBV- cHL cases as controls. There was a significant difference in presence of HLA class I staining between EBV+ and EBV- cases (p<0.0001). We observed normal HLA class I expression in 35% of the EBV+ and in 19% of the EBV- cases. A stronger than normal HLA class I expression was observed in approximately 40% of EBV+ cHL and not in EBV- cHL cases. 36 EBV+ cHL cases contained less than 10 PML-NBs per tumor cell, whereas 16 cases contained more than 10 PML-NBs. The number of PML-NBs was positively correlated to the level of HLA class I expression (p<0.01). The percentage of SATB1 positive cells varied between 0% to 100% in tumor cells and was inversely correlated with the level of HLA class I expression, but only between normal and strong expression (p<0.05). Multivariable analysis indicated that the number of PML-NBs and the percentage of SATB1+ tumor cells are independent factors affecting HLA class I expression in EBV+ cHL. In conclusion, both PML and SATB1 are correlated to HLA class I expression levels in EBV+ cHL.

  4. Bilateral adrenal EBV-associated smooth muscle tumors in a child with a natural killer cell deficiency

    PubMed Central

    Shaw, Rachel K.; Issekutz, Andrew C.; Fraser, Robert; Schmit, Pierre; Morash, Barb; Monaco-Shawver, Linda; Orange, Jordan S.

    2012-01-01

    EBV-associated smooth muscle tumors are found in immunocompromised patients, most commonly HIV/AIDS. We present a 12-year-old girl with the first documented case of EBV-related smooth muscle tumors in the presence of a rare classic NK cell deficiency. This sheds light on the role of NK cells in controlling EBV-related smooth muscle tumors. PMID:22427204

  5. Human Papillomavirus and Epstein-Barr virus co-infection in Cervical Carcinoma in Algerian women

    PubMed Central

    2013-01-01

    Background Despite the fact that the implication of human papillomavirus (HPV) in the carcinogenesis and prognosis of cervical cancer is well established, the impact of a co-infection with high risk HPV (HR-HPV) and Epstein-Barr virus (EBV) is still not fully understood. Methods Fifty eight randomly selected cases of squamous cell carcinomas (SCC) of the uterine cervix, 14 normal cervices specimens, 21 CIN-2/3 and 16 CIN-1 cases were examined for EBV and HPV infections. Detection of HR-HPV specific sequences was carried out by PCR amplification using consensus primers of Manos and by Digene Hybrid Capture. The presence of EBV was revealed by amplifying a 660 bp specific EBV sequence of BALF1. mRNA expression of LMP-1 in one hand and protein levels of BARF-1, LMP-1 and EBNA-1 in the other hand were assessed by RT-PCR and immunoblotting and/or immunohischemistry respectively. Results HR-HPV infection was found in patients with SCC (88%), low-grade (75%) and high grade (95%) lesions compared to only 14% of normal cervix cases. However, 69%, 12.5%, 38.1%, and 14% of SCC, CIN-1, CIN-2/3 and normal cervix tissues, respectively, were EBV infected. The highest co-infection (HR-HPV and EBV) was found in squamous cell carcinoma cases (67%). The latter cases showed 27% and 29% expression of EBV BARF-1 and LMP-1 oncogenes respectively. Conclusion The high rate of HR-HPV and EBV co-infection in SCC suggests that EBV infection is incriminated in cervical cancer progression. This could be taken into account as bad prognosis in this type of cancer. However, the mode of action in dual infection in cervical oncogenesis needs further investigation. PMID:24252325

  6. High Prevalence of Multiple Human Herpesviruses in Saliva from Human Immunodeficiency Virus-Infected Persons in the Era of Highly Active Antiretroviral Therapy

    PubMed Central

    Miller, Craig S.; Berger, Joseph R.; Mootoor, Yunanan; Avdiushko, Sergei A.; Zhu, Hua; Kryscio, Richard J.

    2006-01-01

    Human immunodeficiency virus (HIV) infection is associated with an increased risk for human herpesviruses (HHVs) and their related diseases. Methods for limiting the transmission of HHVs require a better understanding of the prevalence and infectiousness of oral HHVs in HIV-infected patients. We performed quantitative PCR to investigate the prevalence, quantity, risk, and correlates of salivary HHVs from 58 HIV-seropositive individuals in a case control study. HHVs were significantly more prevalent in the salivas of HIV-seropositive persons than in those of the controls (odds ratios [ORs], 4.2 to 26.2; P ≤ 0.008). In HIV-infected patients, Epstein-Barr virus (EBV), human herpesvirus 8 (HHV-8), cytomegalovirus (CMV), and herpes simplex virus type 1 (HSV-1) were detected in 90%, 57%, 31% and 16% of samples, respectively, compared with 48%, 24%, 2%, and 2%, respectively, of samples from controls. Multiple HHVs were observed in 71% of HIV-seropositive persons and only 16% of controls (OR, 13.0; 95% confidence interval, 5.29 to 32.56). HIV-positive patients had significantly higher EBV loads than HIV-negative persons (P < 0.0001). HIV-infected patients with CD4 counts above 200 cells/μl had increased probability for having HHV-8 in saliva (P = 0.009) compared with patients whose counts were less than 200. In contrast, HSV-1, EBV, and CMV were detected more often when CD4 counts were low. High salivary HHV loads were detected for those (n = 7) with oral lesions. These findings suggest that saliva is a potential risk factor for the acquisition of multiple HHVs, and several host factors may function to accelerate HHV reactivation or replication in patients with HIV infection. PMID:16825357

  7. Human Ebola virus infection results in substantial immune activation.

    PubMed

    McElroy, Anita K; Akondy, Rama S; Davis, Carl W; Ellebedy, Ali H; Mehta, Aneesh K; Kraft, Colleen S; Lyon, G Marshall; Ribner, Bruce S; Varkey, Jay; Sidney, John; Sette, Alessandro; Campbell, Shelley; Ströher, Ute; Damon, Inger; Nichol, Stuart T; Spiropoulou, Christina F; Ahmed, Rafi

    2015-04-14

    Four Ebola patients received care at Emory University Hospital, presenting a unique opportunity to examine the cellular immune responses during acute Ebola virus infection. We found striking activation of both B and T cells in all four patients. Plasmablast frequencies were 10-50% of B cells, compared with less than 1% in healthy individuals. Many of these proliferating plasmablasts were IgG-positive, and this finding coincided with the presence of Ebola virus-specific IgG in the serum. Activated CD4 T cells ranged from 5 to 30%, compared with 1-2% in healthy controls. The most pronounced responses were seen in CD8 T cells, with over 50% of the CD8 T cells expressing markers of activation and proliferation. Taken together, these results suggest that all four patients developed robust immune responses during the acute phase of Ebola virus infection, a finding that would not have been predicted based on our current assumptions about the highly immunosuppressive nature of Ebola virus. Also, quite surprisingly, we found sustained immune activation after the virus was cleared from the plasma, observed most strikingly in the persistence of activated CD8 T cells, even 1 mo after the patients' discharge from the hospital. These results suggest continued antigen stimulation after resolution of the disease. From these convalescent time points, we identified CD4 and CD8 T-cell responses to several Ebola virus proteins, most notably the viral nucleoprotein. Knowledge of the viral proteins targeted by T cells during natural infection should be useful in designing vaccines against Ebola virus. PMID:25775592

  8. Human Ebola virus infection results in substantial immune activation.

    PubMed

    McElroy, Anita K; Akondy, Rama S; Davis, Carl W; Ellebedy, Ali H; Mehta, Aneesh K; Kraft, Colleen S; Lyon, G Marshall; Ribner, Bruce S; Varkey, Jay; Sidney, John; Sette, Alessandro; Campbell, Shelley; Ströher, Ute; Damon, Inger; Nichol, Stuart T; Spiropoulou, Christina F; Ahmed, Rafi

    2015-04-14

    Four Ebola patients received care at Emory University Hospital, presenting a unique opportunity to examine the cellular immune responses during acute Ebola virus infection. We found striking activation of both B and T cells in all four patients. Plasmablast frequencies were 10-50% of B cells, compared with less than 1% in healthy individuals. Many of these proliferating plasmablasts were IgG-positive, and this finding coincided with the presence of Ebola virus-specific IgG in the serum. Activated CD4 T cells ranged from 5 to 30%, compared with 1-2% in healthy controls. The most pronounced responses were seen in CD8 T cells, with over 50% of the CD8 T cells expressing markers of activation and proliferation. Taken together, these results suggest that all four patients developed robust immune responses during the acute phase of Ebola virus infection, a finding that would not have been predicted based on our current assumptions about the highly immunosuppressive nature of Ebola virus. Also, quite surprisingly, we found sustained immune activation after the virus was cleared from the plasma, observed most strikingly in the persistence of activated CD8 T cells, even 1 mo after the patients' discharge from the hospital. These results suggest continued antigen stimulation after resolution of the disease. From these convalescent time points, we identified CD4 and CD8 T-cell responses to several Ebola virus proteins, most notably the viral nucleoprotein. Knowledge of the viral proteins targeted by T cells during natural infection should be useful in designing vaccines against Ebola virus.

  9. Antiviral activity of lanatoside C against dengue virus infection.

    PubMed

    Cheung, Yan Yi; Chen, Karen Caiyun; Chen, Huixin; Seng, Eng Khuan; Chu, Justin Jang Hann

    2014-11-01

    Dengue infection poses a serious threat globally due to its recent rapid spread and rise in incidence. Currently, there is no approved vaccine or effective antiviral drug for dengue virus infection. In response to the urgent need for the development of an effective antiviral for dengue virus, the US Drug Collection library was screened in this study to identify compounds with anti-dengue activities. Lanatoside C, an FDA approved cardiac glycoside was identified as a candidate anti-dengue compound. Our data revealed that lanatoside C has an IC50 of 0.19μM for dengue virus infection in HuH-7 cells. Dose-dependent reduction in dengue viral RNA and viral proteins synthesis were also observed upon treatment with increasing concentrations of lanatoside C. Time of addition study indicated that lanatoside C inhibits the early processes of the dengue virus replication cycle. Furthermore, lanatoside C can effectively inhibit all four serotypes of dengue virus, flavivirus Kunjin, alphavirus Chikungunya and Sindbis virus as well as the human enterovirus 71. These findings suggest that lanatoside C possesses broad spectrum antiviral activity against several groups of positive-sense RNA viruses.

  10. Molecular characteristics of diffuse large B-cell lymphoma in human immunodeficiency virus-infected and -uninfected patients in the pre-highly active antiretroviral therapy and pre-rituximab era.

    PubMed

    Morton, Lindsay M; Kim, Clara J; Weiss, Lawrence M; Bhatia, Kishor; Cockburn, Myles; Hawes, Debra; Wang, Sophia S; Chang, Cindy; Altekruse, Sean F; Engels, Eric A; Cozen, Wendy

    2014-03-01

    Human immunodeficiency virus (HIV) infection substantially elevates diffuse large B-cell lymphoma (DLBCL) risk, but its impact on the distinct DLBCL subtypes defined by cell of origin is unclear. We compared DLBCL molecular characteristics and prognosis in 51 HIV-infected and 116 HIV-uninfected cases diagnosed during 1977-2003. Using immunohistochemistry to classify cell of origin based on the Tally algorithm, activated B-cell (ABC)-DLBCL was substantially more common in HIV-infected (83%) than in HIV-uninfected (54%) cases (p < 0.001). Epstein-Barr virus (EBV) was detected in 63% of DLBCLs in HIV-infected cases, occurring almost exclusively in ABC-DLBCL (74% vs. 13% of germinal center B-cell [GCB]-DLBCL, p = 0.002), but was rarely detected in DLBCLs among HIV-uninfected cases (3%). Among HIV-uninfected cases, MYC/IgH [t(8;14)(q24;q32)] and IgH/BCL2 [t(14;18)(q32;q21)] translocations were significantly more common and BCL6/IgH [t(3;14)(q27;q32)] significantly less common in GCB-DLBCL than in ABC-DLBCL (p = 0.010, < 0.001 and = 0.039, respectively). Among HIV-infected cases, translocations other than MYC/IgH [t(8;14)(q24;q32)] (21%) were rare (≤ 6%) and unrelated to cell of origin. ABC-DLBCL was associated with adverse overall survival compared with GCB-DLBCL regardless of HIV status (pHIV-infected = 0.066; pHIV-uninfected = 0.038). Our data demonstrate key differences in the molecular characteristics, cell of origin and prognosis of DLBCL by HIV status in the pre-highly active antiretroviral therapy (HAART) and pre-rituximab era, supporting biologic differences in lymphomagenesis in the presence of HIV. PMID:23772639

  11. A model for persistent infection with Epstein-Barr virus: the stealth virus of human B cells.

    PubMed

    Thorley-Lawson, D A; Babcock, G J

    1999-01-01

    Most adult humans are infected benignly and for life with the herpesvirus Epstein-Barr virus. EBV has been a focus of research because of its status as a candidate tumor virus for a number of lymphomas and carcinomas. In vitro EBV has the ability to establish a latent infection in proliferating B lymphoblasts. This is the only system available for studying human herpesvirus latency in culture and has been extremely useful for elucidating how EBV promotes cellular growth. However, to understand how EBV survives in the healthy host and what goes awry, leading to disease, it is essential to know how EBV establishes and maintains a persistent infection in vivo. Early studies on the mechanism of EBV persistence produced inconclusive and often contradictory results because the techniques available were crude and insensitive. Recent advances in PCR technology and the application of sophisticated cell fractionation techniques have now provided new insights into the behavior of the virus. Most dramatically it has been shown that EBV in vivo does not establish latency in a proliferating lymphoblast, but in a resting memory B cell. The contrasting behaviors of being able to establish a latent infection in proliferating B blasts and resting memory B cells can be resolved in terms of a model where EBV performs its complete life cycle in B lymphocytes. The virus achieves this not by disrupting normal B cell biology but by using it.

  12. Spacecraft Environment May Reduce Resistance To Infection

    NASA Technical Reports Server (NTRS)

    Pierson, Duane L.; Ott, C. Mark; Castro, V. A.; Leal, Melanie; Mehta, Satish K.

    2006-01-01

    Living and working in a spacecraft exposes the crew to a unique environment. This environment includes microgravity, increased radiation, chemical and biological contamination, and a variety of stressors. Disturbances in this balance are often manifested by diminished immunity in astronauts/cosmonauts. Reactivation of Epstein- Barr virus (EBV), cytomegalovirus (CMV), and varicella-zoster virus (VZV) has been used as an indicator of immune status. Reactivation of EBV and VZV were detected and quantified in saliva. CMV was measured in urine. The DNA was extracted using a Qiagen Inc. kit and viral DNA was detected by real time polymerase chain reaction (PCR) based assay with Taqman 7700 (PE Biosystems). Patterns of Epstein-Barr virus (EBV) reactivation in 32 astronauts and 18 healthy age-matched control subjects were characterized by quantifying EBV shedding. Saliva samples were collected before, during, and after 10 space shuttle missions of 5 to 14 d duration. Of 1398 saliva specimens from 32 astronauts, 314 (23%) were positive for EBV DNA. Examination by flight phase showed that 29% of the saliva specimens collected from 28 astronauts before flight were positive for EBV DNA, as were 16% of those collected from 25 astronauts during flight and 16% of those collected after flight from 23 astronauts. The mean number of EBV copies/mL from samples taken during the flights was 417, ten-fold greater (p < 0.05) than the copies from the preflight (40) and post flight (44) phases. In contrast, the control subjects shed EBV DNA with a frequency of 3.7% and mean EBV copies of 40 per mL of saliva. Ten days before flight and on landing day, titers of antibody to EBV viral capsid antigen were significantly (p < 0.05) greater than baseline levels. Increases in the number of viral copies and in the amount of EBV-specific antibody were consistent with EBV reactivation before, during, and after space flight. Similarly, CMV and VZV reactivation increased in response to space flight

  13. Berberine induces mitochondrial apoptosis of EBV-transformed B cells through p53-mediated regulation of XAF1 and GADD45α.

    PubMed

    Park, Ga Bin; Park, Sang Hyun; Kim, Daejin; Kim, Yeong Seok; Yoon, Sung Ho; Hur, Dae Young

    2016-07-01

    Berberine exhibits antiproliferative or cytotoxic effects against various cancers. ROS and wild-type p53 play a critical role in berberine-induced cytotoxic effects. In this study, we investigated the correlation between XAF1 and functional p53 in EBV-transformed B cells or cancerous B cells after treatment with berberine. Berberine decreased cell viability and induced apoptosis through a mitochondria-dependent pathway in EBV-transformed B cells and cancerous B cells, but not in normal peripheral blood mononuclear cells. Activated p53 and its downstream targets XAF1 and GADD45α interacted with PUMA, Bax, and Bim in mitochondria after treatment with berberine. Blocking phosphorylation of p38/JNK MAPK and treatment with PFT-α, a selective p53 inhibitor, effectively prevented apoptosis and the upregulation of phosphorylated p53, XAF1, and GADD45α. NAC, a ROS scavenger, also suppressed berberine-induced mitochondria disruption and the whole apoptotic process via restoration of p53-related proteins and proapoptotic Bcl-2 family proteins. Taken together, our results suggest that ROS generation might be a predisposing event in berberine-induced mitochondrial apoptosis in EBV-transformed B cells through the upregulation of XAF1 and GADD45α expression by MAPK and functional p53.

  14. Down-Regulation of EBV-LMP1 Radio-Sensitizes Nasal Pharyngeal Carcinoma Cells via NF-κB Regulated ATM Expression

    PubMed Central

    Xiao, Lanbo; Tang, Min; Liu, Liyu; Li, Zijian; Deng, Mengyao; Sun, Lunquan; Cao, Ya

    2011-01-01

    Background The latent membrane protein 1 (LMP1) encoded by EBV is expressed in the majority of EBV-associated human malignancies and has been suggested to be one of the major oncogenic factors in EBV-mediated carcinogenesis. In previous studies we experimentally demonstrated that down-regulation of LMP1 expression by DNAzymes could increase radiosensitivity both in cells and in a xenograft NPC model in mice. Results In this study we explored the molecular mechanisms underlying the radiosensitization caused by the down-regulation of LMP1 in nasopharyngeal carcinoma. It was confirmed that LMP1 could up-regulate ATM expression in NPCs. Bioinformatic analysis of the ATM ptomoter region revealed three tentative binding sites for NF-κB. By using a specific inhibitor of NF-κB signaling and the dominant negative mutant of IkappaB, it was shown that the ATM expression in CNE1-LMP1 cells could be efficiently suppressed. Inhibition of LMP1 expression by the DNAzyme led to attenuation of the NF-κB DNA binding activity. We further showed that the silence of ATM expression by ATM-targeted siRNA could enhance the radiosensitivity in LMP1 positive NPC cells. Conclusions Together, our results indicate that ATM expression can be regulated by LMP1 via the NF-κB pathways through direct promoter binding, which resulted in the change of radiosensitivity in NPCs. PMID:22096476

  15. Berberine induces mitochondrial apoptosis of EBV-transformed B cells through p53-mediated regulation of XAF1 and GADD45α.

    PubMed

    Park, Ga Bin; Park, Sang Hyun; Kim, Daejin; Kim, Yeong Seok; Yoon, Sung Ho; Hur, Dae Young

    2016-07-01

    Berberine exhibits antiproliferative or cytotoxic effects against various cancers. ROS and wild-type p53 play a critical role in berberine-induced cytotoxic effects. In this study, we investigated the correlation between XAF1 and functional p53 in EBV-transformed B cells or cancerous B cells after treatment with berberine. Berberine decreased cell viability and induced apoptosis through a mitochondria-dependent pathway in EBV-transformed B cells and cancerous B cells, but not in normal peripheral blood mononuclear cells. Activated p53 and its downstream targets XAF1 and GADD45α interacted with PUMA, Bax, and Bim in mitochondria after treatment with berberine. Blocking phosphorylation of p38/JNK MAPK and treatment with PFT-α, a selective p53 inhibitor, effectively prevented apoptosis and the upregulation of phosphorylated p53, XAF1, and GADD45α. NAC, a ROS scavenger, also suppressed berberine-induced mitochondria disruption and the whole apoptotic process via restoration of p53-related proteins and proapoptotic Bcl-2 family proteins. Taken together, our results suggest that ROS generation might be a predisposing event in berberine-induced mitochondrial apoptosis in EBV-transformed B cells through the upregulation of XAF1 and GADD45α expression by MAPK and functional p53. PMID:27121748

  16. Rabbits immunized with Epstein-Barr virus gH/gL or gB recombinant proteins elicit higher serum virus neutralizing activity than gp350.

    PubMed

    Cui, Xinle; Cao, Zhouhong; Chen, Quanyi; Arjunaraja, Swadhinya; Snow, Andrew L; Snapper, Clifford M

    2016-07-25

    Epstein-Barr virus (EBV) is the primary cause of infectious mononucleosis and has been strongly implicated in the etiology of multiple epithelial and lymphoid cancers, such as nasopharyngeal carcinoma, gastric carcinoma, Hodgkin lymphoma, Burkitt lymphoma, non-Hodgkin lymphoma and post-transplant lymphoproliferative disorder. There is currently no licensed prophylactic vaccine for EBV. Most efforts to develop prophylactic vaccines have focused on EBV gp350, which binds to CD21/CD35 to gain entry into B cells, and is a major target of serum neutralizing antibody in EBV seropositive humans. However, a recombinant monomeric gp350 protein failed to prevent EBV infection in a phase II clinical trial. Thus, alternative or additional target antigens may be necessary for a successful prophylactic vaccine. EBV gH/gL and gB proteins coordinately mediate EBV fusion and entry into B cells and epithelial cells, strongly suggesting that vaccination with these proteins might elicit antibodies that will prevent EBV infection. We produced recombinant trimeric and monomeric EBV gH/gL heterodimeric proteins and a trimeric EBV gB protein, in addition to tetrameric and monomeric gp350(1-470) proteins, in Chinese hamster ovary cells. We demonstrated that vaccination of rabbits with trimeric and monomeric gH/gL, trimeric gB, and tetrameric gp350(1-470) induced serum EBV-neutralizing titers, using cultured human B cells, that were >100-fold, 20-fold, 18-fold, and 4-fold higher, respectively, than monomeric gp350(1-470). These data strongly suggest a role for testing EBV gH/gL and EBV gB in a future prophylactic vaccine to prevent EBV infection of B cells, as well as epithelial cells.

  17. Persistent Infection Drives the Development of CD8+ T Cells Specific for Late Lytic Infection Antigens in Lymphocryptovirus-Infected Macaques and Epstein-Barr Virus-Infected Humans▿

    PubMed Central

    Orlova, Nina; Wang, Fred; Fogg, Mark H.

    2011-01-01

    We examined the CD8+ T cell repertoire against lytic infection antigens in rhesus macaques persistently infected with the Epstein-Barr virus (EBV)-related lymphocryptovirus (rhLCV). CD8+ T cells specific for late (L) antigens were detected at rates comparable to those for early antigens and were associated with increasing duration of infection. L antigen-specific CD8+ T cells were also readily detected in adult, EBV-positive humans. Thus, viral major histocompatibility complex class I (MHCI) immune evasion genes expressed during lytic LCV infection do not prevent L-specific CD8+ T cell development over time during persistent infection. PMID:21917961

  18. Massive Activation of Archaeal Defense Genes during Viral Infection

    PubMed Central

    Voet, Marleen; Sismeiro, Odile; Dillies, Marie-Agnes; Jagla, Bernd; Coppée, Jean-Yves; Sezonov, Guennadi; Forterre, Patrick; van der Oost, John; Lavigne, Rob

    2013-01-01

    Archaeal viruses display unusually high genetic and morphological diversity. Studies of these viruses proved to be instrumental for the expansion of knowledge on viral diversity and evolution. The Sulfolobus islandicus rod-shaped virus 2 (SIRV2) is a model to study virus-host interactions in Archaea. It is a lytic virus that exploits a unique egress mechanism based on the formation of remarkable pyramidal structures on the host cell envelope. Using whole-transcriptome sequencing, we present here a global map defining host and viral gene expression during the infection cycle of SIRV2 in its hyperthermophilic host S. islandicus LAL14/1. This information was used, in combination with a yeast two-hybrid analysis of SIRV2 protein interactions, to advance current understanding of viral gene functions. As a consequence of SIRV2 infection, transcription of more than one-third of S. islandicus genes was differentially regulated. While expression of genes involved in cell division decreased, those genes playing a role in antiviral defense were activated on a large scale. Expression of genes belonging to toxin-antitoxin and clustered regularly interspaced short palindromic repeat (CRISPR)-Cas systems was specifically pronounced. The observed different degree of activation of various CRISPR-Cas systems highlights the specialized functions they perform. The information on individual gene expression and activation of antiviral defense systems is expected to aid future studies aimed at detailed understanding of the functions and interplay of these systems in vivo. PMID:23698312

  19. Intrapleural tissue plasminogen activator and deoxyribonuclease therapy for pleural infection.

    PubMed

    Piccolo, Francesco; Popowicz, Natalia; Wong, Donny; Lee, Yun Chor Gary

    2015-06-01

    Pleural infection remains a global health burden associated with significant morbidity. Drainage of the infected pleural fluid is important but can often be hindered by septations and loculations. Intrapleural fibrinolytic therapy alone, to break pleural adhesions, has shown no convincing advantages over placebo in improving clinical outcome. Deoxyribonucleoprotein from degradation of leukocytes contributes significantly to high viscosity of infected pleural fluid. Recombinant deoxyribonuclease (DNase) is effective in reducing pleural fluid viscosity in pre-clinical studies. The combination of tissue plasminogen activator (tPA) and DNase was effective in animal model experiments of empyema. The benefits were established in a randomized clinical trial: those (n=48) treated with tPA/DNase had significantly improved radiological outcomes and reduced need of surgery and duration of hospital stay. A longitudinal observational series of 107 patients further confirmed the effectiveness and safety of tPA/DNase therapy, including its use as 'rescue therapy' when patients failed to respond to antibiotics and chest tube drainage. Overall, a short course of intrapleural tPA (10 mg) and DNase (5 mg) therapy provides a cure in over 90% of patients without requiring surgery. The treatment stimulates pleural fluid formation, enhances radiographic clearance and resolution of systemic inflammation. Serious complications are uncommon; pleural bleeding requiring transfusion occurred in ~2% of cases. Pain can occur, especially with the first dose. Treatment is contraindicated in those with significant bleeding diathesis or a bronchopleural fistula. Future research is required to optimize dosing regimens and in refining patient selection. PMID:26150913

  20. EBV, HCMV, HHV6, and HHV7 Screening in Bone Marrow Samples from Children with Acute Lymphoblastic Leukemia

    PubMed Central

    Morales-Sánchez, A.; Pompa-Mera, E. N.; Fajardo-Gutiérrez, A.; Alvarez-Rodríguez, F. J.; Bekker-Méndez, V. C.; Flores-Chapa, J. de Diego; Flores-Lujano, J.; Jiménez-Hernández, E.; Peñaloza-González, J. G.; Rodríguez-Zepeda, M. C.; Torres-Nava, J. R.; Velázquez-Aviña, M. M.; Amador-Sánchez, R.; Alvarado-Ibarra, M.; Reyes-Zepeda, N.; Espinosa-Elizondo, R. M.; Pérez-Saldivar, M. L.; Núñez-Enríquez, J. C.; Mejía-Aranguré, J. M.; Fuentes-Pananá, E. M.

    2014-01-01

    Acute lymphoblastic leukemia (ALL) is the most common cancer in childhood worldwide and Mexico has reported one of the highest incidence rates. An infectious etiology has been suggested and supported by epidemiological evidences; however, the identity of the involved agent(s) is not known. We considered that early transmitted lymphotropic herpes viruses were good candidates, since transforming mechanisms have been described for them and some are already associated with human cancers. In this study we interrogated the direct role of EBV, HCMV, HHV6, and HHV7 human herpes viruses in childhood ALL. Viral genomes were screened in 70 bone marrow samples from ALL patients through standard and a more sensitive nested PCR. Positive samples were detected only by nested PCR indicating a low level of infection. Our result argues that viral genomes were not present in all leukemic cells, and, hence, infection most likely was not part of the initial genetic lesions leading to ALL. The high statistical power of the study suggested that these agents are not involved in the genesis of ALL in Mexican children. Additional analysis showed that detected infections or coinfections were not associated with prognosis. PMID:25309913

  1. EBV, HCMV, HHV6, and HHV7 screening in bone marrow samples from children with acute lymphoblastic leukemia.

    PubMed

    Morales-Sánchez, A; Pompa-Mera, E N; Fajardo-Gutiérrez, A; Alvarez-Rodríguez, F J; Bekker-Méndez, V C; Flores-Chapa, J de Diego; Flores-Lujano, J; Jiménez-Hernández, E; Peñaloza-González, J G; Rodríguez-Zepeda, M C; Torres-Nava, J R; Velázquez-Aviña, M M; Amador-Sánchez, R; Alvarado-Ibarra, M; Reyes-Zepeda, N; Espinosa-Elizondo, R M; Pérez-Saldivar, M L; Núñez-Enríquez, J C; Mejía-Aranguré, J M; Fuentes-Pananá, E M

    2014-01-01

    Acute lymphoblastic leukemia (ALL) is the most common cancer in childhood worldwide and Mexico has reported one of the highest incidence rates. An infectious etiology has been suggested and supported by epidemiological evidences; however, the identity of the involved agent(s) is not known. We considered that early transmitted lymphotropic herpes viruses were good candidates, since transforming mechanisms have been described for them and some are already associated with human cancers. In this study we interrogated the direct role of EBV, HCMV, HHV6, and HHV7 human herpes viruses in childhood ALL. Viral genomes were screened in 70 bone marrow samples from ALL patients through standard and a more sensitive nested PCR. Positive samples were detected only by nested PCR indicating a low level of infection. Our result argues that viral genomes were not present in all leukemic cells, and, hence, infection most likely was not part of the initial genetic lesions leading to ALL. The high statistical power of the study suggested that these agents are not involved in the genesis of ALL in Mexican children. Additional analysis showed that detected infections or coinfections were not associated with prognosis. PMID:25309913

  2. Sequence analysis of EBV immune evasion gene BNLF2a in EBV associated tumors and healthy individuals from nasopharyngeal carcinoma endemic and non-endemic regions of China.

    PubMed

    Liu, Song; Wang, Xiaofeng; Shu, Jun; Zhao, Zhenzhen; Sun, Zhifu; Luo, Bing

    2015-11-01

    BNLF2a is an Epstein-Barr virus (EBV) immune evasion gene. Its protein is located in the endoplasmic reticulum (ER) membrane, and can inhibit the antigen transporting function of TAP, thereby perturbing the immune response to EBV in lytic and prelatent phase. In order to explore whether the polymorphism of BNLF2a gene has a role in different types of EBV associated tumors, we conducted complete sequencing of the gene BNLF2a in 408 cases of EBV positive tumors (76 lymphomas, 45 gastric carcinomas, and 85 nasopharyngeal carcinomas in northern China and 27 lymphomas, 30 gastric carcinomas, and 57 nasopharyngeal carcinomas in southern China) and throat washings from healthy individuals (39 in northern China and 49 in southern China). Two main variant types of BNLF2a were identified. Type BNLF2a-A, which was similar to B95-8, was dominant in all sub-populations (66.7-100%) in this study. Type BNLF2a-B was characterized by the mutations at position 8 and 40. The variation patterns of BNLF2a were significantly different between samples from northern and southern China (P < 0.05), and between the tumors and healthy donor samples from the northern China (P < 0.0167). Type BNLF2a-B was more frequent in healthy donors of northern China (33.3%), and the proportion of this type was higher in the northern than in the southern NPCs. These data demonstrate that the BNLF2a gene is highly conserved, and its polymorphism is geographically restricted. Type BNLF2a-B is more prevalent in northern China and may be less tumor transformative.

  3. Mitral valve repair for active culture positive infective endocarditis

    PubMed Central

    Doukas, G; Oc, M; Alexiou, C; Sosnowski, A W; Samani, N J; Spyt, T J

    2006-01-01

    Objective To describe the clinical and echocardiographic outcome after mitral valve (MV) repair for active culture positive infective MV endocarditis. Patients and methods Between 1996 and 2004, 36 patients (mean (SD) age 53 (18) years) with positive blood culture up to three weeks before surgery (or positive culture of material removed at operation) and intraoperative evidence of endocarditis underwent MV repair. Staphylococci and streptococci were the most common pathogens. All patients had moderate or severe mitral regurgitation (MR). Mean New York Heart Association (NYHA) class was 2.3 (1.0). Follow up was complete (mean 38 (19) months). Results Operative mortality was 2.8% (one patient). At follow up, endocarditis has not recurred. One patient developed severe recurrent MR and underwent valve replacement and one patient had moderate MR. There were two late deaths, both non‐cardiac. Kaplan‐Meier five year freedom from recurrent moderate to severe MR, freedom from repeat operation, and survival were 94 (4)%, 97 (3)%, and 93 (5)%, respectively. At the most recent review the mean NYHA class was 1.17 (0.3) (p < 0.0001). At the latest echocardiographic evaluation, left atrial diameters, left ventricular end diastolic diameter, and MV diameter were significantly reduced (p < 0.05) compared with preoperative values. Conclusions MV repair for active culture positive endocarditis is associated with low operative mortality and provides satisfactory freedom from recurrent infection, freedom from repeat operation, and survival. Hence, every effort should be made to repair infected MVs and valves should be replaced only when repair is not possible. PMID:15951395

  4. Antimicrobial activity of Lactobacillus against microbial flora of cervicovaginal infections

    PubMed Central

    Dasari, Subramanyam; Shouri, Raju Naidu Devanaboyaina; Wudayagiri, Rajendra; Valluru, Lokanatha

    2014-01-01

    Objective To assess the probiotic nature of Lactobacillus in preventing cervical pathogens by studying the effectiveness of antimicrobial activity against vaginal pathogens. Methods Lactobacilli were isolated from healthy vaginal swabs on selective media and different pathogenic bacteria were isolated by using different selective media. The Lactobacillus strains were tested for the production of hydrogen peroxide and antimicrobial compounds along with probiotic properties. Results Of the 10 isolated Lactobacillus strains, strain 1, 3 and 6 are high hydrogen peroxide producers and the rest were low producers. Results of pH and amines tests indicated that pH increased with fishy odour in the vaginal fluids of cervicovaginal infection patients when compared with vaginal fluids of healthy persons. The isolates were found to be facultative anaerobic, Gram-positive, non-spore-forming, non-capsule forming and catalase-negative bacilli. The results of antimicrobial activity of compounds indicated that 280 and 140 µg/mL was the minimum concentration to inhibit the growth of both pathogens and test organisms respectively. Conclusions The results demonstrated that Lactobacillus producing antimicrobial compounds inhibits the growth of cervical pathogens, revealing that the hypothesis of preventing vaginal infection by administering probiotic organisms has a great appeal to patients, which colonize the vagina to help, restore and maintain healthy vagina.

  5. Uncommon illness from common infections.

    PubMed Central

    Christian, C. L.

    1988-01-01

    Individual common infectious agents such as EBV, CMV and HBV have well characterized relationships to a variety of acute and chronic disease states; the host and/or environment variables underlying this clinical heterogeneity are not known. Given the high frequency of these viral infections in the general population, there should be a cautious interpretation of antiviral serological data. PMID:3332514

  6. Differential cellular localization of Epstein-Barr virus and human cytomegalovirus in the colonic mucosa of patients with active or quiescent inflammatory bowel disease.

    PubMed

    Ciccocioppo, Rachele; Racca, Francesca; Scudeller, Luigia; Piralla, Antonio; Formagnana, Pietro; Pozzi, Lodovica; Betti, Elena; Vanoli, Alessandro; Riboni, Roberta; Kruzliak, Peter; Baldanti, Fausto; Corazza, Gino Roberto

    2016-02-01

    The role of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) in the exacerbation of inflammatory bowel disease (IBD) is still uncertain. We prospectively investigated the presence of EBV and HCMV infection in both epithelial and immune cells of colonic mucosa of IBD patients, both refractory and responders to standard therapies, in comparison with patients suffering from irritable bowel syndrome who were considered as controls, by using quantitative real-time polymerase chain reaction, immunohistochemistry and in situ hybridization, in an attempt to assess viral localization, DNA load, life cycle phase and possible correlation with disease activity indexes. We obtained clear evidence of the presence of high DNA loads of both viruses in either enterocytes or immune cells of refractory IBD patients, whereas we observed low levels in the responder group and an absence of detectable copies in all cell populations of controls. Remarkably, the values of EBV and HCMV DNA in inflamed mucosa were invariably higher than in non-inflamed areas in both IBD groups, and the EBV DNA loads in the cell populations of diseased mucosa of refractory IBD patients positively correlated with the severity of mucosal damage and clinical indexes of activity. Moreover, EBV infection resulted the most prevalent either alone or in combination with HCMV, while immunohistochemistry and in situ hybridization did not allow us to distinguish between the different phases of viral life cycle. Finally, as regards treatment, these novel findings could pave the way for the use of new antiviral molecules in the treatment of this condition. PMID:26659090

  7. [Laboratory diagnosis of Epstein-Barr virus infection].

    PubMed

    Siennicka, Joanna; Trzcińska, Agnieszka

    2007-01-01

    Laboratory confirmation of EBV infection requires proper methods and schema of investigation adequate to aim of diagnostic procedure. In paper the results of routine diagnostic tests of EBV infection performed in Department of Virology NIH in 2005-2006 years was included and also, evaluation of usefulness of different laboratory methods was done. Based on results of ELISA tests 10,7% routine investigated subjects was classified as primary EBV infection, 20,1% was seronegative, 7,4% was classified as reactivation of latent infection and serological markers in 45,6% subjects pointed past EBV infection. Positive result of PCR method was obtain in 11,2% samples subjected of routine laboratory investigation. Comparison of specific and non-specific serological methods results (ELISA versus tests of heterophile antibodies) showed the high percentage of false negative results in children tested by non-specific tests. PCR results in serum samples from patients with primary infection (confirmed by serological tests) were positive in 15% cases only. Based on analyzed results it could be stated that reliable confirmation of infectious mononucleosis, as primary EBV infection, is detection of specific IgM antibodies and in case of heterophile antibodies tests the possibility of false negative results, mainly in children, must be taken into account. The most proper samples for PCR method are whole blood, sections of tissue or cells from swabs. PMID:18078121

  8. A microRNA signature profile in EBV+ diffuse large B-cell lymphoma of the elderly

    PubMed Central

    de Andrade, Tathiana Azevedo; Evangelista, Adriane Feijo; Campos, Antonio Hugo Froes; Poles, Wagner Augusto; Borges, Natalia Morais; Camillo, Claudia Malheiros Coutinho; Soares, Fernando Augusto; Vassallo, Jose; Paes, Roberto Pinto; Zerbini, Maria Claudia; Scapulatempo, Cristovam; Alves, Antonio Correa

    2014-01-01

    Currently, there is no characteristic microRNA (miRNA) expression pattern in Epstein-Barr virus+ diffuse large B-cell lymphoma of the elderly (EBV+DLBCLe). This study aims to characterize a signature profile and identify miRNAs that can be used as biomarkers and alternative therapeutic targets for EBV+DLBCLe. Seventy-one DLBCL patients aged 50 years and older were included and four EBV+ and four EBV– samples were analyzed in two miRNA array platforms (pilot study). A larger multicenter cohort (29 EBV+DLBCLe and 65 EBV–DLBCL patients) was used to validate the results by real-time polymerase chain reaction. In the pilot study, 9% of DLBCL were EBV+DLBCLe by in situ hybridization. In multicenter study, EBV+DLBCLe group showed a predominance of non-germinal center B-cell origin. Overall survival duration of EBV+DLBCLe was significantly inferior to that of EBV–DLBCL patients. We found 10 deregulated miRNAs in the two groups, but only seven were statistically different. We confirmed overexpression of hsa-miR-126, hsa-miR-146a, hsa-miR-146b, hsa-miR-150, and hsa-miR-222 and underexpression of hsa-miR-151 in EBV+DLBCLe cases compared to EBV–DLBCL cases. Hsa-miR-146b and hsa-miR-222 showed high specificity for identifying EBV+DLBCLe. The present study proposed a miRNA signature for EBV+DLBCLe and our findings suggest that hsa-miR-146b and hsa-miR-222 could be biomarkers and therapeutic targets. PMID:25544772

  9. Epstein-Barr virus infection of CR2-transfected epithelial cells reveals the presence of MHC class II on the virion.

    PubMed

    Knox, P G; Young, L S

    1995-10-20

    Epithelial cell lines transfected with the Epstein-Barr virus (EBV) receptor CR2 are susceptible to infection by EBV. Following infection with certain EBV strains we found that these cells became positive for MHC class II. The class II was confirmed as being of viral and not target cell origin by immunostaining with HLA-specific monoclonal antibodies. Electron microscopic immunogold staining confirmed the presence of MHC class II on the surface of the virion. While some MHC class I was also found on the EB virion, other cell surface molecules were absent. Dual color immunofluorescence and confocal microscopy analysis demonstrated colocalization of class II with EBV-encoded structural proteins (MA and VCA) in infected epithelial cells. However, preincubation of EBV with antibodies against either MHC class I or MHC class II failed to affect either EBV binding or EBV infection. The presence of MHC on the surface of the EB virion may be a consequence of the intracellular pathways through which productive virus exits from the cell and may influence the target cell tropism of EBV. PMID:7483258

  10. Activation of a Pollenin Promoter upon Nematode Infection

    PubMed Central

    Karimi, M.; de Oliveira Manes, C.-L.; Van Montagu, M.; Gheysen, G.

    2002-01-01

    Three glycine-rich protein genes of Arabidopsis thaliana (Atgrp-6, Atgrp-7, and Atgrp-8) that correspond to putative genes coding for pollenins (AtolnB;2, AtolnB;3, and AtolnB;4, respectively) are expressed predominantly in the anthers and, more specifically, in the tapetum layer. Tapetal cells are responsible for nutrition of developing pollen grains and show some functional similarities to nematode feeding sites (NFS) induced in plant roots by sedentary parasitic nematodes. The aim of this study was to analyze promoter activity of the Atgrp genes in NFS. Transformed Arabidopsis plants containing a promoter-ß-glucuronidase (gus) fusion of the Atgrp-7 gene were inoculated with the root-knot nematode Meloidogyne incognita and the cyst nematode Heterodera schachtii. GUS assays were performed at different time points after infection. Histochemical analysis revealed an up-regulation of Atgrp-7-gus expression 3 days after inoculation in the feeding sites of both nematodes. Maximal Atgrp-7-gus staining levels in NFS were observed 1 week after nematode infection. PMID:19265912

  11. The interplay between Epstein-Barr virus and B lymphocytes: implications for infection, immunity, and disease.

    PubMed

    Hatton, Olivia L; Harris-Arnold, Aleishia; Schaffert, Steven; Krams, Sheri M; Martinez, Olivia M

    2014-05-01

    Human B cells are the primary targets of Epstein-Barr virus (EBV) infection. In most cases, EBV infection is asymptomatic because of a highly effective host immune response, but some individuals develop self-limiting infectious mononucleosis, while others develop EBV-associated lymphoid or epithelial malignancies. The viral and immune factors that determine the outcome of infection are not understood. The EBV life cycle includes a lytic phase, culminating in the production of new viral particles, and a latent phase, during which the virus remains largely silent for the lifetime of the host in memory B cells. Thus, in healthy individuals, there is a tightly orchestrated interplay between EBV and the host that allows the virus to persist. To promote viral persistence, EBV has evolved a variety of strategies to modulate the host immune response including inhibition of immune cell function, blunting of apoptotic pathways, and interfering with antigen processing and presentation pathways. In this article, we focus on mechanisms by which dysregulation of the host B cell and immune modulation by the virus can contribute to development of EBV+ B cell lymphomas. PMID:24619311

  12. Reactivation of Epstein-Barr virus during early infection with human immunodeficiency virus.

    PubMed Central

    Rahman, M A; Kingsley, L A; Atchison, R W; Belle, S; Breinig, M C; Ho, M; Rinaldo, C R

    1991-01-01

    Reactivation of Epstein-Barr virus (EBV) in early human immunodeficiency virus (HIV) infection was investigated in 49 homosexual men who seroconverted to HIV (cases) as compared with 49 matched controls who remained seronegative to HIV during a longitudinal study. EBV infection was reactivated in cases 6 months, but not 12 months, prior to HIV seroconversion as compared with controls and remained reactivated during 18 months of follow-up after HIV seroconversion, as shown by increases in immunoglobulin (Ig) G antibody titers to EBV early antigen. Antibody titers to EBV viral capsid antigen did not differ between cases and controls prior to the time of seroconversion to HIV but were significantly increased among cases by the first seropositive study visit and remained elevated during the 18 months after HIV seroconversion. Total serum IgG levels were increased in cases at the visit of seroconversion, and during 18 months of follow-up, but did not correlate with enhanced IgG production specific for EBV antigens. Significant decreases in numbers of CD4+ cells and increases in numbers of CD8+ cells during this early phase of HIV infection were not associated with changes in patterns of EBV antibody responses. Reactivation of EBV beginning 6 months before HIV seroconversion may have implications regarding the role of this herpesvirus in the pathogenesis of HIV. PMID:1650790

  13. Epstein-Barr virus infection in vitro can rescue germinal center B cells with inactivated immunoglobulin genes.

    PubMed

    Chaganti, Sridhar; Bell, Andrew I; Pastor, Noelia Begue; Milner, Anne E; Drayson, Mark; Gordon, John; Rickinson, Alan B

    2005-12-15

    Immunoglobulin genotyping of Epstein-Barr virus (EBV)-positive posttransplantation lymphoproliferative disease has suggested that such lesions often arise from atypical post-germinal center B cells, in some cases carrying functionally inactivated immunoglobulin genes. To investigate whether EBV can rescue cells that are failed products of the somatic hypermutation process occurring in germinal centers (GCs), we isolated GC cells from tonsillar cell suspensions and exposed them to EBV in vitro. Screening more than 100 EBV-transformed cell lines of GC origin identified 6 lines lacking surface immunoglobulin, a phenotype never seen among lines derived from circulating naive or memory B cells. Furthermore, 3 of the 6 surface immunoglobulin-negative GC lines carried inactivating mutations in the immunoglobulin H (IgH) variable gene sequence. The ability of EBV to rescue aberrant products of the germinal center reaction in vitro strengthens the probability that a parallel activity contributes to EBV's lymphomagenic potential in vivo.

  14. Modes of infection and oncogenesis by the Epstein-Barr virus.

    PubMed

    Murata, Takayuki; Sato, Yoshitaka; Kimura, Hiroshi

    2014-07-01

    The EBV is a human γ-herpesvirus associated with various neoplasms. It is responsible for causing cancers of B, T, and NK cells as well as cells of epithelial origin. Such diversity in target cells and the complicated steps of oncogenesis are perplexing when we speculate about the mechanisms of action of EBV-positive cancers. Here, we first note three common features that contribute to the development and maintenance of EBV-positive cancers: effects of EBV oncogenes, immunosuppression and evasion/exploitation of the immune system, and genetic and epigenetic predisposition/alteration of the host genome. Then, we demonstrate the mechanisms of oncogenesis and the means by which each EBV-positive cancer develops, with particular focus on the mode of EBV infection. The EBV has two alternative life cycles: lytic and latent. The latter is categorized into four programs (latency types 0-III) in which latent viral genes are expressed differentially depending on the tissue of origin and state of cells. The production of viral latent genes tends to decrease with an increase in time, and, in an approximate manner, the expression levels of viral genes are inversely correlated with the degree of abnormalities in the host genome. Occasional execution of the viral lytic cycle also contributes to oncogenesis. Understanding this life cycle of the EBV and its relevance in oncogenesis may provide valuable clues to the development of effective therapies for the associated cancers. PMID:24578255

  15. Overexpression of PIN1 Enhances Cancer Growth and Aggressiveness with Cyclin D1 Induction in EBV-Associated Nasopharyngeal Carcinoma

    PubMed Central

    Xu, Meng; Cheung, Chartia Ching-Mei; Chow, Chit; Lun, Samantha Wei-Man; Cheung, Siu-Tim; Lo, Kwok-Wai

    2016-01-01

    Background Nasopharyngeal carcinoma (NPC) is a peculiar Epstein Barr virus (EBV)-associated malignancy that is prevalent in South-East Asia. Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (PIN1) isomerizes specific phosphorylated amino acid residues, which makes it an important regulator in cell survival and apoptosis. In this study, we investigated the contribution made by PIN1 in NPC tumorigenesis and PIN1’s potential role as a therapeutic target. Methods The expression of PIN1 was examined in a panel of NPC cell lines, xenografts and primary tumors. The functional roles of PIN1 in NPC cells were elucidated by the knockdown and overexpression of PIN1 in in vitro and in vivo nude mice models by siRNA and lenti-viral transfection, respectively. The antitumor effects of the PIN1 inhibitor Juglone in NPC cells were also evaluated. Results We revealed the consistent overexpression of PIN1 in almost all EBV-associated NPC cell lines, xenografts and primary tumors. PIN1 suppression was capable of inhibiting cyclin D1 expression and activating caspase-3 in NPC cells. It positively regulated NPC cell proliferation, colony formation and anchorage-independent growth. The inhibition of PIN1 suppressed tumor growth in vitro and in vivo. Conclusions This study demonstrates the oncogenic role of PIN1 in NPC tumorigenesis, and shows that its overexpression can enhance tumor cell growth via the upregulation of cyclinD1. Our findings inform the development of novel treatments targeting PIN1 for NPC patients. PMID:27258148

  16. Infection.

    PubMed

    Miclau, Theodore; Schmidt, Andrew H; Wenke, Joseph C; Webb, Lawrence X; Harro, Janette M; Prabhakara, Ranjani; Shirtliff, Mark E

    2010-09-01

    Musculoskeletal infection is a clinical problem with significant direct healthcare costs. The prevalence of infection after closed, elective surgery is frequently estimated to be less than 2%, but in severe injuries, posttraumatic infection rates have been reported as 10% or greater. Although clinical infections are found outside the realm of medical devices, it is clear that the enormous increase of infections associated with the use of implants presents a major challenge worldwide. This review summarizes recent advances in the understanding, diagnosis, and treatment of musculoskeletal infections.

  17. Infection of lymphocytes by a virus that aborts cytotoxic T lymphocyte activity and establishes persistent infection

    PubMed Central

    1991-01-01

    For viruses to establish persistent infections in their hosts, they must possess some mechanism for evading clearance by the immune system. When inoculated into adult immunocompetent mice, wild-type lymphocytic choriomeningitis virus (LCMV ARM) induces a CD8(+)-mediated cytotoxic T lymphocyte (CTL) response that clears the infection within 7-14 d (CTL+ [P-]). By contrast, variant viruses isolated from lymphoid tissues of persistently infected mice fail to induce a CTL response and are thus able to establish a persistent infection in adult mice (CTL- [P+]). This report compares the interaction of CTL+ (P-) and CTL- (P+) viruses with cells of the immune system. Both types of virus initially bind to 2-4% of CD4+ and CD8+ T lymphocytes and replicate within cells of both subsets. The replication of CTL- (P+) and CTL+ (P-) viruses in lymphocytes in vivo is similar for the first 5 d after initiating infection. Thereafter, in mice infected with CTL- (P+) variants, lymphocytes retain viral genetic information, and infectious virus can be recovered throughout the animals' lives. In contrast, when adult mice are infected with wild-type CTL+ (P-) LCMV ARM, virus is not recovered from lymphocytes for greater than 7 d after infection. A CD8(+)-mediated anti-LCMV CTL response is induced in such mice. Clearance of infected lymphocytes is produced by these LCMV-specific CTLs, as shown by their ability to lyse lymphocytes expressing LCMV determinants in vitro and the fact that depletion of CD8+ lymphocytes before infection with CTL+ (P-) viruses results in levels of infected lymphocytes similar to those found in undepleted CTL- (P+)-infected mice. Hence, CTL-mediated lysis of T lymphocytes carrying infectious virus is a critical factor determining whether virus persists or the infection is terminated. PMID:1905339

  18. Expression of epstein-barr virus encoded nuclear antigen 1 in benign and malignant tissues harbouring EBV.

    PubMed Central

    Oudejans, J J; Dukers, D F; Jiwa, N M; van den Brule, A J; Grässer, F A; de Bruin, P C; Horstman, A; Vos, W; van Gorp, J; Middeldorp, J M; Meijer, C J

    1996-01-01

    AIMS: To determine levels of expression of Epstein-Barr virus (EBV) nuclear antigen 1 (EBNA1) in benign and malignant tissues harbouring EBV in relation to EBNA1 promoter usage. METHODS: Expression of EBNA1 was investigated by means of immunohistochemistry using a mixture of two EBNA1 specific monoclonal antibodies, 1H4-1 and 2B4-1. The presence of EBV was detected by EBER1/2 RNA in situ hybridisation. Detection of promoter specific EBNA1 transcripts was by RT-PCR analysis. RESULTS: EBNA1 positive cells were detected in all 20 EBV associated B cell lymphomas, 18 of which had arisen in immunocompromised patients; in eight of nine EBV associated T cell lymphomas; in 11 of 27 EBV positive cases of Hodgkin's disease; and in reactive lymphoid tissue harbouring EBV, including four cases of infectious mononucleosis. A diffuse EBNA1 staining pattern was observed in most of the EBV associated B cell lymphomas and was comparable with the EBER1/2 staining pattern. In the T cell lymphomas the number of EBNA1 positive cells was usually considerably less than the number of EBER1/2 positive ones. RT-PCR analysis revealed that in tumours with restricted EBNA1 expression-that is, T cell lymphomas and Hodgkin's disease lesions, EBNA1 transcripts were usually generated only by the F/Q promoter, whereas in B cell lymphomas EBNA1 transcripts were usually generated by both the C/W and F/Q promoters. CONCLUSIONS: EBNA1 is expressed in all types of tissue harbouring EBV, but the level of expression varies greatly. This may be the result of differential promoter usage. Images PMID:8944608

  19. Acute Acalculous Cholecystitis by Epstein-Barr Virus Infection: A Rare Association

    PubMed Central

    Vieira, Maria; Couto, Cristiana; Coelho, Maria D.; Laranjeira, Carla

    2015-01-01

    Acute acalculous cholecystitis (AAC) is a rare complication of Epstein Barr virus (EBV) infection, with only a few cases reported among pediatric population. This clinical condition is frequently associated with a favorable outcome and, usually, a surgical intervention is not required. We report a 16-year-old girl who presented with AAC following primary EBV infection. The diagnosis of AAC was documented by clinical and ultrasonographic examination, whereas EBV infection was confirmed serologically. A conservative treatment was performed, with a careful monitoring and serial ultrasonographic examinations, which led to the clinical improvement of the patient. Pediatricians should be aware of the possible association between EBV and AAC, in order to offer the patients an appropriate management strategy. PMID:26753086

  20. How the heterogeneous infection rate effect on the epidemic spreading in activity-driven network

    NASA Astrophysics Data System (ADS)

    Han, Dun; Li, Dandan; Chen, Chao; Sun, Mei

    2016-01-01

    In this paper, we research the impact of the heterogeneous infection rate on the epidemic spread in the activity-driven networks. By using the mean field approximation, the epidemic threshold is theoretically obtained. Several immunization strategies that could curb the epidemic spread are presented. Based on the theoretical analysis and simulation results, we obtain that the epidemic would be prevented effectively if the infection rate strongly correlates with the individual activity. However, if infection rate has a little correlation with the individual activity, most of the individuals may be infected. In addition, the epidemic can be suppressed soon if the individuals with high activity are immunized preferentially.

  1. Epstein-Barr virus Rta-mediated transactivation of p21 and 14-3-3σ arrests cells at the G1/S transition by reducing cyclin E/CDK2 activity.

    PubMed

    Huang, Sheng-Yen; Hsieh, Min-Jie; Chen, Chu-Ying; Chen, Yen-Ju; Chen, Jen-Yang; Chen, Mei-Ru; Tsai, Ching-Hwa; Lin, Su-Fang; Hsu, Tsuey-Ying

    2012-01-01

    Many herpesviral immediate-early proteins promote their robust lytic phase replications by hijacking the cell cycle machinery. Previously, lytic replication of Epstein-Barr virus (EBV) was found to be concurrent with host cell cycle arrest. In this study, we showed that ectopic expression of EBV immediate-early protein Rta in HEp-2 cells resulted in increased G1/S population, hypophosphorylation of pRb and decreased incorporation of 5-bromo-2'-deoxyuridine. In addition, EBV Rta transcriptionally upregulates the expressions of p21 and 14-3-3σ in HEp-2 cells, 293 cells and nasopharyngeal carcinoma TW01 cells. Although p21 and 14-3-3σ are known targets for p53, Rta-mediated p21 and 14-3-3σ transactivation can be detected in the absence of p53. In addition, results from luciferase reporter assays indicated that direct binding of Rta to either promoter sequences is not required for activation. On the other hand, a special class of Sp1-responsive elements was involved in Rta-mediated transcriptional activation on both promoters. Finally, Rta-induced p21 expression diminished the activity of CDK2/cyclin E complex, and, Rta-induced 14-3-3σ expression sequestered CDK1 and CDK2 in the cytoplasm. Based on these results, we hypothesize that through the disruption of CDK1 and CDK2 activities, EBV Rta might contribute to cell cycle arrest in EBV-infected epithelial cells during viral reactivation. PMID:21918011

  2. Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection

    PubMed Central

    Agrati, C; Castilletti, C; Casetti, R; Sacchi, A; Falasca, L; Turchi, F; Tumino, N; Bordoni, V; Cimini, E; Viola, D; Lalle, E; Bordi, L; Lanini, S; Martini, F; Nicastri, E; Petrosillo, N; Puro, V; Piacentini, M; Di Caro, A; Kobinger, G P; Zumla, A; Ippolito, G; Capobianchi, M R

    2016-01-01

    Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells. PMID:27031961

  3. Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection.

    PubMed

    Agrati, C; Castilletti, C; Casetti, R; Sacchi, A; Falasca, L; Turchi, F; Tumino, N; Bordoni, V; Cimini, E; Viola, D; Lalle, E; Bordi, L; Lanini, S; Martini, F; Nicastri, E; Petrosillo, N; Puro, V; Piacentini, M; Di Caro, A; Kobinger, G P; Zumla, A; Ippolito, G; Capobianchi, M R

    2016-01-01

    Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells.

  4. Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection.

    PubMed

    Agrati, C; Castilletti, C; Casetti, R; Sacchi, A; Falasca, L; Turchi, F; Tumino, N; Bordoni, V; Cimini, E; Viola, D; Lalle, E; Bordi, L; Lanini, S; Martini, F; Nicastri, E; Petrosillo, N; Puro, V; Piacentini, M; Di Caro, A; Kobinger, G P; Zumla, A; Ippolito, G; Capobianchi, M R

    2016-01-01

    Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells. PMID:27031961

  5. Genome-wide Analysis of Epstein-Barr Virus (EBV) Integration and Strain in C666-1 and Raji Cells

    PubMed Central

    Xiao, Kai; Yu, Zhengyuan; Li, Xiayu; Li, Xiaoling; Tang, Ke; Tu, Chaofeng; Qi, Peng; Liao, Qianjin; Chen, Pan; Zeng, Zhaoyang; Li, Guiyuan; Xiong, Wei

    2016-01-01

    EBV is a key risk factor for many malignancy diseases such as nasopharyngeal carcinoma (NPC) and Burkitt lymphoma (BL). EBV integration has been reported, but its scale and impact to cancer development is remains unclear. C666-1 (NPC cell line) and Raji (BL cell line) are commonly studied EBV-positive cancer cells. A rare few EBV integration sites in Raji were found in previous research by traditional methods. To deeply survey EBV integration, we sequenced C666-1 and Raji whole genomes by the next generation sequencing (NGS) technology and a total of 909 breakpoints were detected in the two cell lines. Moreover, we observed that the number of integration sites was positive correlated with the total amount of chromosome structural variations (SVs) and copy number structural variations (CNVs), and most breakpoints located inside or nearby genome structural variations regions. It suggested that host genome instability provided an opportunity for EBV integration on one hand and the integration aggravated host genome instability on the other hand. Then, we respectively assembled the C666-1 and Raji EBV strains which would be useful resources for EBV-relative studies. Thus, we report the most comprehensive characterization of EBV integration in NPC cell and BL cell, and EBV shows the wide range and random integration to increase the tumorigenesis. The NGS provides an incomparable level of resolution on EBV integration and a convenient approach to obtain viral strain compared to any research technology before. PMID:26819646

  6. Host shutoff is a conserved phenotype of gammaherpesvirus infection and is orchestrated exclusively from the cytoplasm.

    PubMed

    Covarrubias, Sergio; Richner, Justin M; Clyde, Karen; Lee, Yeon J; Glaunsinger, Britt A

    2009-09-01

    Lytic infection with the two human gammaherpesviruses, Kaposi's sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV), leads to significant depletion of the cellular transcriptome. This host shutoff phenotype is driven by the conserved herpesviral alkaline exonuclease, termed SOX in KSHV and BGLF5 in EBV, which in gammaherpesviruses has evolved the genetically separable ability to target cellular mRNA. We now show that host shutoff is also a prominent consequence of murine gammaherpesvirus 68 (MHV68) infection, which is widely used as a model system to study pathogenesis of these viruses in vivo. The effector of MHV68-induced host shutoff is its SOX homolog, here termed muSOX. There is remarkable functional conservation of muSOX host shutoff activities with those of KSHV SOX, including the recently described ability of SOX to induce mRNA hyperadenylation in the nucleus as well as cause nuclear relocalization of the poly(A) binding protein. SOX and muSOX localize to both the nucleus and cytoplasm of infected cells. Using spatially restricted variants of these proteins, we go on to demonstrate that all known host shutoff-related activities of SOX and muSOX are orchestrated exclusively from the cytoplasm. These results have important mechanistic implications for how SOX and muSOX target nascent cellular transcripts in the nucleus. Furthermore, our findings establish MHV68 as a new, genetically tractable model to study host shutoff.

  7. Aryl-alkyl-lysines: Membrane-Active Small Molecules Active against Murine Model of Burn Infection.

    PubMed

    Ghosh, Chandradhish; Manjunath, Goutham B; Konai, Mohini M; Uppu, Divakara S S M; Paramanandham, Krishnamoorthy; Shome, Bibek R; Ravikumar, Raju; Haldar, Jayanta

    2016-02-12

    Infections caused by drug-resistant Gram-negative pathogens continue to be significant contributors to human morbidity. The recent advent of New Delhi metallo-β-lactamase-1 (blaNDM-1) producing pathogens, against which few drugs remain active, has aggravated the problem even further. This paper shows that aryl-alkyl-lysines, membrane-active small molecules, are effective in treating infections caused by Gram-negative pathogens. One of the compounds of the study was effective in killing planktonic cells as well as dispersing biofilms of Gram-negative pathogens. The compound was extremely effective in disrupting preformed biofilms and did not select resistant bacteria in multiple passages. The compound retained activity in different physiological conditions and did not induce any toxic effect in female Balb/c mice until concentrations of 17.5 mg/kg. In a murine model of Acinetobacter baumannii burn infection, the compound was able to bring the bacterial burden down significantly upon topical application for 7 days. PMID:27624962

  8. Hepatitis C Virus Infection Is Associated With an Increased Risk of Active Tuberculosis Disease

    PubMed Central

    Wu, Ping-Hsun; Lin, Yi-Ting; Hsieh, Kun-Pin; Chuang, Hung-Yi; Sheu, Chau-Chyun

    2015-01-01

    Abstract Tuberculosis (TB) and hepatitis C virus (HCV) infection contribute to major disease mortality and morbidity worldwide. However, the causal link between HCV infection and TB risk remains unclear. We conducted a population-based cohort study to elucidate the association between HCV infection and TB disease by analyzing Taiwan National Health Insurance Database. We enrolled 5454 persons with HCV infection and 54,274 age- and sex-matched non-HCV-infected persons between January 1998 and December 2007. Time-dependent Cox proportional hazards regression analysis was used to measure the association between HCV infection and active TB disease. Incidence rate of active TB disease was higher among HCV infection than in control (134.1 vs 89.1 per 100,000 person-years; incidence rate ratio 1.51; P = 0.014). HCV infection was significantly associated with active TB disease in multivariate Cox regression (adjusted hazard ratio [HR] 3.20; 95% confidence interval [CI], 1.85–5.53; P < 0.001) and competing death risk event analysis (adjusted HR 2.11; 95% CI, 1.39–3.20; P < 0.001). Multivariate stratified analysis further revealed that HCV infection was a risk of active TB disease in most strata. This nationwide cohort study suggests that HCV infection is associated with a higher risk of developing active TB disease. PMID:26287416

  9. Epstein-Barr Virus Infection in Chronically Inflamed Periapical Granulomas

    PubMed Central

    Makino, Kosuke; Takeichi, Osamu; Hatori, Keisuke; Imai, Kenichi; Ochiai, Kuniyasu; Ogiso, Bunnai

    2015-01-01

    Periapical granulomas are lesions around the apex of a tooth caused by a polymicrobial infection. Treatment with antibacterial agents is normally performed to eliminate bacteria from root canals; however, loss of the supporting alveolar bone is typically observed, and tooth extraction is often selected if root canal treatment does not work well. Therefore, bacteria and other microorganisms could be involved in this disease. To understand the pathogenesis of periapical granulomas more precisely, we focused on the association with Epstein-Barr virus (EBV) using surgically removed periapical granulomas (n = 32). EBV DNA was detected in 25 of 32 periapical granulomas (78.1%) by real-time PCR, and the median number of EBV DNA copies was approximately 8,688.01/μg total DNA. In contrast, EBV DNA was not detected in healthy gingival tissues (n = 10); the difference was statistically significant according to the Mann-Whitney U test (p = 0.0001). Paraffin sections were also analyzed by in situ hybridization to detect EBV-encoded small RNA (EBER)-expressing cells. EBER was detected in the cytoplasm and nuclei of B cells and plasma cells in six of nine periapical granulomas, but not in healthy gingival tissues. In addition, immunohistochemical analysis for latent membrane protein 1 (LMP-1) of EBV using serial tissue sections showed that LMP-1-expressing cells were localized to the same areas as EBER-expressing cells. These data suggest that B cells and plasma cells in inflamed granulomas are a major source of EBV infection, and that EBV could play a pivotal role in controlling immune cell responses in periapical granulomas. PMID:25884725

  10. Glycolytic control of vacuolar-type ATPase activity: A mechanism to regulate influenza viral infection

    SciTech Connect

    Kohio, Hinissan P.; Adamson, Amy L.

    2013-09-15

    As new influenza virus strains emerge, finding new mechanisms to control infection is imperative. In this study, we found that we could control influenza infection of mammalian cells by altering the level of glucose given to cells. Higher glucose concentrations induced a dose-specific increase in influenza infection. Linking influenza virus infection with glycolysis, we found that viral replication was significantly reduced after cells were treated with glycolytic inhibitors. Addition of extracellular ATP after glycolytic inhibition restored influenza infection. We also determined that higher levels of glucose promoted the assembly of the vacuolar-type ATPase within cells, and increased vacuolar-type ATPase proton-transport activity. The increase of viral infection via high glucose levels could be reversed by inhibition of the proton pump, linking glucose metabolism, vacuolar-type ATPase activity, and influenza viral infection. Taken together, we propose that altering glucose metabolism may be a potential new approach to inhibit influenza viral infection. - Highlights: • Increased glucose levels increase Influenza A viral infection of MDCK cells. • Inhibition of the glycolytic enzyme hexokinase inhibited Influenza A viral infection. • Inhibition of hexokinase induced disassembly the V-ATPase. • Disassembly of the V-ATPase and Influenza A infection was bypassed with ATP. • The state of V-ATPase assembly correlated with Influenza A infection of cells.

  11. HHV-8 and EBV-positive intravascular lymphoma: an unusual presentation of extracavitary primary effusion lymphoma

    PubMed Central

    Crane, Genevieve M.; Ambinder, Richard F.; Shirley, Courtney M.; Fishman, Elliot K.; Kasamon, Yvette L.; Taube, Janis M.; Borowitz, Michael J.; Duffield, Amy S.

    2014-01-01

    Intravascular lymphomas are rare and aggressive hematolymphoid tumors. Here we describe a human herpesvirus type-8/Kaposi sarcoma-associated herpesvirus (HHV-8/KSHV) and Epstein-Barr virus (EBV) positive intravascular lymphoma. The patient was a 59 year-old HIV-positive man who presented with diarrhea, abdominal pain, fevers, night sweats, and weight loss. Radiographic studies of the abdomen and pelvis revealed numerous subcentimeter nodules within the subcutaneous fat that lacked connection to the skin. An excisional biopsy demonstrated large atypical cells within vessels in the deep subcutaneous fat, and many of the vessels contained extensive organizing thrombi. The atypical cells lacked strong expression of most B-cell markers but were positive for MUM-1 and showed partial expression of several T-cell markers. An immunohistochemical stain for HHV-8 and an in situ hybridization for EBV were both positive in the neoplastic cells. The disease had a rapidly progressive and fatal course. This lymphoma appears to represent an entirely intravascular form of primary effusion lymphoma, and highlights the propensity for HHV-8 and EBV-positive lymphoid neoplasms to show aberrant expression of T-cell markers, illustrates the utility of skin biopsies for the diagnosis of intravascular lymphoma, and suggests that biopsies to evaluate for intravascular lymphoma should be relatively deep and include subcutaneous fat. PMID:24525514

  12. Risk factors for multiple sclerosis and associations with anti-EBV antibody titers.

    PubMed

    Mouhieddine, Tarek H; Darwish, Hala; Fawaz, Lama; Yamout, Bassem; Tamim, Hani; Khoury, Samia J

    2015-05-01

    Multiple sclerosis (MS) is an inflammatory demyelination of the central nervous system. We investigated the prevalence of EBV seropositivity and other known risk factors for MS (age, smoking, low vitamin D) and their effect on anti-EBV antibody titers. We retrospectively studied 249 MS patients receiving care at the American University of Beirut Medical Center and 230 controls, during 2010-2014. EBV seropositivity was higher in MS patients compared to controls for both anti-VCA (99.5%; 97.2%) and anti-EBNA-1 (96.3%; 89.4%), and the titers were significantly higher in MS patients. MS patients had a significantly lower vitamin D level (15.5 ± 8.3 ng/ml) compared to controls (20.4 ± 11.3 ng/ml). The proportion of heavy smokers and overweight individuals was significantly higher in MS patients. Lebanese MS patients have risk factors similar to those in western countries. Older age and female gender were associated with a higher anti-VCA titer and male gender with a higher anti-EBNA-1.

  13. The c-Cbl proto-oncoprotein downregulates EBV LMP2A signaling

    PubMed Central

    Ikeda, Masato; Longnecker, Richard

    2009-01-01

    Latent membrane protein 2A (LMP2A) of Epstein-Barr virus (EBV) plays a key role in regulating viral latency and EBV pathogenesis by functionally mimicking signals induced by the B-cell receptor (BCR) altering normal B cell development. As c-Cbl ubiquitin ligase (E3) is a critical negative regulator in the BCR signal pathway, the role of c-Cbl in the function and formation of the LMP2A signalsome was examined. c-Cbl promoted LMP2A degradation through ubiquitination, specifically degraded the Syk protein tyrosine kinase in the presence of LMP2A, and inhibited LMP2A induction of the EBV lytic cycle. Our earlier studies indicated that LMP2A-dependent Lyn degradation was mediated by Nedd4-family E3s in LMP2A expressing cells. Combine with these new findings, we propose a model in which c-Cbl and Nedd4-family E3s cooperate to degrade target proteins at discrete steps in the function of the LMP2A signalosome. PMID:19081591

  14. Primary bone natural killer/T cell lymphoma, nasal type without EBV infection: a case report

    PubMed Central

    Tian, Chen; Wang, Yafei; Zhu, Lei; Yu, Yong; Zhang, Yizhuo

    2015-01-01

    Primary bone NK/T cell lymphoma is very rare. We report a case of 52-year-old man of primary bone NK/T cell lymphoma and then progressed to NK leukemia. The patient had low-grade fever for 4-month, and Ultrasonic B revealed a diffuse hepatosplenomegaly without lymphadenopathy. PET scanning showed increased FDG uptake in many bones of the whole body. The diagnosis was established by bone specimen. These neoplastic cells demonstrated a typical immunophenotype of CD56, CD3, CD2 and MPO positive, and CD5, CD20, CD30, PAX-5, CD4 and CD8 negative. Primary bone ENKTL is very rare; it should be made with the combination of clinical feature, PET-CT image, and pathological characteristics, and should be distinguished from other lymphomas or leukemia involved in bone. PMID:26823813

  15. Diagnostic moléculaire du Cytomégalovirus (CMV), de l’herpès virus humain de type 6 (HHV6) et d’Epstein-Barr virus (EBV) par PCR en temps réel chez les femmes enceintes VIH séropositives et séronégatives à Ouagadougou, Burkina Faso

    PubMed Central

    Ouedraogo, Alice Rogomenoma; Kabre, Madeleine; Bisseye, Cyrille; Zohoncon, Théodora Mahoukèdè; Asshi, Maleki; Soubeiga, Serge Théophile; Diarra, Birama; Traore, Lassina; Djigma, Florencia Wendkuuni; Ouermi, Djénéba; Pietra, Virginio; Barro, Nicolas; Simpore, Jacques

    2016-01-01

    Introduction Les herpès virus EBV, CMV et HHV-6 sont des virus qui évoluent sous le modèle pandémique et sont responsables d’infections congénitales pouvant provoquer des séquelles graves chez les nouveau-nés. L’objectif de cette étude était de déterminer les prévalences de CMV, EBV et HHV-6 chez les femmes enceintes VIH(+) et VIH(-) à Ouagadougou. Méthodes Dans cette étude 200 échantillons de plasma sanguin de femmes enceintes dont 100 femmes VIH(+) et 100 femmes VIH(-) ont été diagnostiqués par PCR multiplex en temps réel pour les trois infections (EBV, CMV et HHV-6). Résultats Sur l’ensemble des 200 échantillons analysés, 18 (9,0%) étaient positifs à au moins un des trois virus, 12 (6,0%) étaient positifs au EBV, 13 (6,5%) au CMV et 12 (6,0%) positifs au HHV-6. Parmi les 18 cas d’infections, nous avons trouvé 10 cas (55,6%) de coïnfections dont 90,0% (9/10) d’infection multiple EBV/CMV/HHV6 et 10,0% de coinfection EBV/HHV6. Le taux d’infection HHVs était plus élevé chez les femmes VIH(-) que celles VIH(+) (12,0% versus 6,0%). Parmi les VIH(+), la PCR a révélé 7,1% (soit 6/85) d’infection HHVs chez celles qui n’étaient pas sous ARV contre 0% chez celles sous ARV. Conclusion Les herpès virus sont fréquents chez les femmes enceintes au Burkina Faso et pourraient constituer une menace chez ces dernières à cause des complications et des risques d’infection pour le nouveau-né. PMID:27800078

  16. Identification of GLA/SE as an effective adjuvant for the induction of robust humoral and cell-mediated immune responses to EBV-gp350 in mice and rabbits.

    PubMed

    Heeke, Darren S; Lin, Rui; Rao, Eileen; Woo, Jennifer C; McCarthy, Michael P; Marshall, Jason D

    2016-05-17

    Childhood infection with Epstein-Barr virus (EBV) is often asymptomatic and may result in mild flu-like symptoms, but exposure during adolescence and young adulthood can lead to acute infectious mononucleosis (AIM) with a pathology characterized by swollen lymph nodes, sore throat, and severe fatigue lasting weeks or months. A vaccine targeting the envelope glycoprotein gp350 adjuvanted with aluminum hydroxide complexed with the TLR4 agonist monophosphoryl lipid A (MPLA) achieved a 78% reduction in AIM incidence in a small phase II trial of college-age individuals, but development of this vaccine was halted by the manufacturer. Here, we report the evaluation in mice and rabbits of an EBV-gp350 vaccine combined with an adjuvant composed of the synthetic TLR4 agonist glucopyranosyl lipid A (GLA) integrated into stable emulsion (SE). In mice, GLA/SE-adjuvanted gp350 generated high IgG titers (both IgG1 and IgG2a/c subtypes), elevated EBV-neutralizing antibody titers, and robust poly-functional anti-gp350 CD4(+) T cell responses. In addition, GLA/SE routinely demonstrated superior performance over aluminum hydroxide in all immunological readouts, including induction of durable neutralizing antibody titers out to at least 1 year post-vaccination. Both components of the GLA/SE adjuvant were found to be required to get optimal responses in both arms of the immune response: specifically, SE for neutralizing antibodies and GLA for induction of T cell responses. Furthermore, this vaccine also elicited high neutralizing antibody titers in a second species, rabbit. These promising results suggest that clinical development of a vaccine comprised of EBV-gp350 plus GLA/SE has the potential to prevent AIM in post-adolescents. PMID:27085175

  17. 18F-FDG PET/CT Findings in Acute Epstein-Barr Virus Infection Mimicking Malignant Lymphoma

    PubMed Central

    Ørbæk, Mathilde; Graff, Jesper; Markova, Elena; Kronborg, Gitte; Lebech, Anne-Mette

    2016-01-01

    We present a case demonstrating the diagnostic work-up and follow-up of a patient with acute Epstein-Barr virus (EBV) infection in which the clinical picture and imaging on 18F-FDG PET/CT mimicked malignant lymphoma. Follow-up 18F-FDG PET/CT scan in the patient performed 7 weeks after the abnormal scan revealed complete resolution of the metabolically active disease in the neck, axillas, lung hili, and spleen. This case highlights inflammation as one of the most well established false positives when interpreting 18F-FDG PET/CT scans. PMID:27187482

  18. (18)F-FDG PET/CT Findings in Acute Epstein-Barr Virus Infection Mimicking Malignant Lymphoma.

    PubMed

    Ørbæk, Mathilde; Graff, Jesper; Markova, Elena; Kronborg, Gitte; Lebech, Anne-Mette

    2016-01-01

    We present a case demonstrating the diagnostic work-up and follow-up of a patient with acute Epstein-Barr virus (EBV) infection in which the clinical picture and imaging on (18)F-FDG PET/CT mimicked malignant lymphoma. Follow-up (18)F-FDG PET/CT scan in the patient performed 7 weeks after the abnormal scan revealed complete resolution of the metabolically active disease in the neck, axillas, lung hili, and spleen. This case highlights inflammation as one of the most well established false positives when interpreting (18)F-FDG PET/CT scans. PMID:27187482

  19. COX-2 induces lytic reactivation of EBV through PGE2 by modulating the EP receptor signaling pathway.

    PubMed

    Gandhi, Jaya; Gaur, Nivedita; Khera, Lohit; Kaul, Rajeev; Robertson, Erle S

    2015-10-01

    Inflammation is one of the predisposing factors known to be associated with Epstein Barr Virus (EBV) mediated tumorigenesis. However it is not well understood whether inflammation in itself plays a role in regulating the life cycle of this infectious agent. COX-2, a key mediator of the inflammatory processes is frequently over-expressed in EBV positive cancer cells. In various tumors, PGE2 is the principle COX-2 regulated downstream product which exerts its effects on cellular processes through the EP1-4 receptors. In this study, we further elucidated how upregulated COX-2 levels can modulate the events in EBV life cycle related to latency-lytic reactivation. Our data suggest a role for upregulated COX-2 on modulation of EBV latency through its downstream effector PGE2. This study demonstrates a role for increased COX-2 levels in modulation of EBV latency. This is important for understanding the pathogenesis of EBV-associated cancers in people with chronic inflammatory conditions. PMID:26057147

  20. COX-2 induces lytic reactivation of EBV through PGE2 by modulating the EP receptor signaling pathway.

    PubMed

    Gandhi, Jaya; Gaur, Nivedita; Khera, Lohit; Kaul, Rajeev; Robertson, Erle S

    2015-10-01

    Inflammation is one of the predisposing factors known to be associated with Epstein Barr Virus (EBV) mediated tumorigenesis. However it is not well understood whether inflammation in itself plays a role in regulating the life cycle of this infectious agent. COX-2, a key mediator of the inflammatory processes is frequently over-expressed in EBV positive cancer cells. In various tumors, PGE2 is the principle COX-2 regulated downstream product which exerts its effects on cellular processes through the EP1-4 receptors. In this study, we further elucidated how upregulated COX-2 levels can modulate the events in EBV life cycle related to latency-lytic reactivation. Our data suggest a role for upregulated COX-2 on modulation of EBV latency through its downstream effector PGE2. This study demonstrates a role for increased COX-2 levels in modulation of EBV latency. This is important for understanding the pathogenesis of EBV-associated cancers in people with chronic inflammatory conditions.

  1. Macrophage Activation Redirects Yersinia-Infected Host Cell Death from Apoptosis to Caspase-1-Dependent Pyroptosis

    PubMed Central

    Bergsbaken, Tessa; Cookson, Brad T

    2007-01-01

    Infection of macrophages by Yersinia species results in YopJ-dependent apoptosis, and naïve macrophages are highly susceptible to this form of cell death. Previous studies have demonstrated that macrophages activated with lipopolysaccharide (LPS) prior to infection are resistant to YopJ-dependent cell death; we found this simultaneously renders macrophages susceptible to killing by YopJ− Yersinia pseudotuberculosis (Yptb). YopJ− Yptb-induced macrophage death was dependent on caspase-1 activation, resulting in rapid permeability to small molecules, followed by membrane breakdown and DNA damage, and accompanied by cleavage and release of proinflammatory interleukin-18. Induction of caspase-1-dependent death, or pyroptosis, required the bacterial type III translocon but none of its known translocated proteins. Wild-type Yptb infection also triggered pyroptosis: YopJ-dependent activation of proapoptotic caspase-3 was significantly delayed in activated macrophages and resulted in caspase-1-dependent pyroptosis. The transition to susceptibility was not limited to LPS activation; it was also seen in macrophages activated with other Toll-like receptor (TLR) ligands and intact nonviable bacteria. Yptb infection triggered macrophage activation and activation of caspase-1 in vivo. Y. pestis infection of activated macrophages also stimulated caspase-1 activation. These results indicate that host signaling triggered by TLR and other activating ligands during the course of Yersinia infection redirects both the mechanism of host cell death and the downstream consequences of death by shifting from noninflammatory apoptosis to inflammatory pyroptosis. PMID:17983266

  2. Neutrophil cell death, activation and bacterial infection in cystic fibrosis

    PubMed Central

    Watt, A; Courtney, J; Moore, J; Ennis, M; Elborn, J

    2005-01-01

    Background: Cystic fibrosis (CF) is characterised by chronic endobronchial bacterial infection and neutrophil mediated inflammation. Neutrophil apoptosis is essential for the resolution of inflammation. This study assessed the relationship between levels of neutrophil apoptosis and sputum microbiology in matched clinically stable patients with CF. Methods: Sputum was induced from 34 patients (nine with no Gram negative infection, 10 colonised with Pseudomonas aeruginosa, 10 with Burkholderia cenocepacia, and five with other infections). Apoptotic neutrophils measured by flow cytometric Annexin V/propidium iodide staining and morphology were similar in all groups. Results: Patients infected with P aeruginosa or B cenocepacia had a significantly lower percentage of viable neutrophils in the sputum than those with no Gram negative infection (Kruskal-Wallis p = 0.01, median (interquartile range (IQR)) 14.2% (9.4–21.6), 15.8% (12.3–19.5), and 48.4% (23.0–66.4); p = 0.003 and p = 0.002, respectively). They also had significantly higher levels of secondary necrotic granulocytes in sputum than patients with no Gram negative infection (Kruskal-Wallis p<0.0001, median (IQR) 55.5% (48.4–64.5), 50.4% (44.6–61.9), and 24.8% (14.4–30.5); p<0.0001 and p<0.0001, respectively). Neutrophils (x106/g sputum) in P aeruginosa infected patients (Kruskal-Wallis p = 0.05, median (IQR) 6.3 (3.5–12.7)) and B cenocepacia infected patients (5.7 (1.5–14.5)) were significantly higher than in the group with no Gram negative infection (0.5 (0.5–4.3), p = 0.03 and 0.04, respectively). Conclusion: These results suggest that cell death and clearance may be altered in patients with CF colonised with P aeruginosa and B cenocepacia compared with those with no Gram negative infection. PMID:16061707

  3. Decreased Flight Activity in Culex pipiens (Diptera: Culicidae) Naturally Infected With Culex flavivirus.

    PubMed

    Newman, Christina M; Anderson, Tavis K; Goldberg, Tony L

    2016-01-01

    Insect-specific flaviviruses (ISFVs) commonly infect vectors of mosquito-borne arboviruses. To investigate whether infection with an ISFV might affect mosquito flight behavior, we quantified flight behavior in Culex pipiens L. naturally infected with Culex flavivirus (CxFV). We observed a significant reduction in the scotophase (dark hours) flight activity of CxFV-positive mosquitoes relative to CxFV-negative mosquitoes, but only a marginal reduction in photophase (light hours) flight activity, and no change in the circadian pattern of flight activity. These results suggest that CxFV infection alters the flight activity of naturally infected Cx. pipiens most dramatically when these vectors are likely to be host seeking and may therefore affect the transmission of medically important arboviruses.

  4. Determination of Urinary Neopterin/Creatinine Ratio to Distinguish Active Tuberculosis from Latent Mycobacterium tuberculosis Infection

    PubMed Central

    Eisenhut, Michael; Hargreaves, Dougal S.; Scott, Anne; Housley, David; Walters, Andrew; Mulla, Rohinton

    2016-01-01

    Background. Biomarkers to distinguish latent from active Mycobacterium (M.) tuberculosis infection in clinical practice are lacking. The urinary neopterin/creatinine ratio can quantify the systemic interferon-gamma effect in patients with M. tuberculosis infection. Methods. In a prospective observational study, urinary neopterin levels were measured by enzyme linked immunosorbent assay in patients with active tuberculosis, in people with latent M. tuberculosis infection, and in healthy controls and the urinary neopterin/creatinine ratio was calculated. Results. We included a total of 44 patients with M. tuberculosis infection and nine controls. 12 patients had active tuberculosis (8 of them culture-confirmed). The median age was 15 years (range 4.5 to 49). Median urinary neopterin/creatinine ratio in patients with active tuberculosis was 374.1 micromol/mol (129.0 to 1072.3), in patients with latent M. tuberculosis infection it was 142.1 (28.0 to 384.1), and in controls it was 146.0 (40.3 to 200.0), with significantly higher levels in patients with active tuberculosis (p < 0.01). The receiver operating characteristics curve had an area under the curve of 0.84 (95% CI 0.70 to 0.97) (p < 0.01). Conclusions. Urinary neopterin/creatinine ratios are significantly higher in patients with active tuberculosis compared to patients with latent infection and may be a significant predictor of active tuberculosis in patients with M. tuberculosis infection. PMID:27433370

  5. Effects of immunomodulators on functional activity of innate immunity cells infected with Streptococcus pneumoniae.

    PubMed

    Plekhova, N G; Kondrashova, N M; Somova, L M; Drobot, E I; Lyapun, I N

    2015-02-01

    Low activity of bactericidal enzymes was found in innate immunity cells infected with S. pneumonia. The death of these cells was fastened under these conditions. On the contrary, treatment with antibiotic maxifloxacin was followed by an increase in activity of bactericidal enzymes in phagocytes and induced their death via necrosis. Analysis of the therapeutic properties of immunomodulators tinrostim and licopid in combination with maxifloxacin showed that these combinations correct functional activity of cells infected with S. pneumonia. PMID:25708326

  6. The Epstein-Barr Virus Protein BRLF1 Activates S Phase Entry through E2F1 Induction

    PubMed Central

    Swenson, Jennifer J.; Mauser, Amy E.; Kaufmann, William K.; Kenney, Shannon C.

    1999-01-01

    The Epstein-Barr Virus (EBV) immediate-early protein BRLF1 is one of two transactivators which mediate the switch from latent to lytic replication in EBV-infected cells. DNA viruses often modulate the function of critical cell cycle proteins to maximize the efficiency of virus replication. Here we have examined the effect of BRLF1 on cell cycle progression. A replication-deficient adenovirus expressing BRLF1 (AdBRLF1) was used to infect normal human fibroblasts and various epithelial cell lines. BRLF1 expression induced S phase entry in contact-inhibited fibroblasts and in the human osteosarcoma cell line U-2 OS. AdBRLF1 infection produced a dramatic increase in the level of E2F1 but not E2F4. In contrast, the levels of Rb, p107, and p130 were decreased in AdBRLF1-infected cells. Electrophoretic mobility shift assays confirmed an increased level of free E2F1 in the AdBRLF1-infected human fibroblasts. Consistent with the previously described effect of E2F1, AdBRLF1-infected fibroblasts had increased levels of p53 and p21 and died by apoptosis. BRLF1-induced activation of E2F1 may be required for efficient EBV lytic replication, since at least one critical viral replication gene (the viral DNA polymerase) is activated by E2F (C. Liu, N. D. Sista, and J. S. Pagano, J. Virol. 70:2545–2555, 1996). PMID:10400750

  7. Salamanders increase their feeding activity when infected with the pathogenic chytrid fungus Batrachochytrium dendrobatidis.

    PubMed

    Hess, Alexandra; McAllister, Caroline; DeMarchi, Joseph; Zidek, Makenzie; Murone, Julie; Venesky, Matthew D

    2015-10-27

    Immune function is a costly line of defense against parasitism. When infected with a parasite, hosts frequently lose mass due to these costs. However, some infected hosts (e.g. highly resistant individuals) can clear infections with seemingly little fitness losses, but few studies have tested how resistant hosts mitigate these costly immune defenses. We explored this topic using eastern red-backed salamanders Plethodon cinereus and the fungal pathogen Batrachochytrium dendrobatidis (Bd). Bd is generally lethal for amphibians, and stereotypical symptoms of infection include loss in mass and deficits in feeding. However, individuals of P. cinereus can clear their Bd infections with seemingly few fitness costs. We conducted an experiment in which we repeatedly observed the feeding activity of Bd-infected and non-infected salamanders. We found that Bd-infected salamanders generally increased their feeding activity compared to non-infected salamanders. The fact that we did not observe any differences in mass change between the treatments suggests that increased feeding might help Bd-infected salamanders minimize the costs of an effective immune response.

  8. Salamanders increase their feeding activity when infected with the pathogenic chytrid fungus Batrachochytrium dendrobatidis.

    PubMed

    Hess, Alexandra; McAllister, Caroline; DeMarchi, Joseph; Zidek, Makenzie; Murone, Julie; Venesky, Matthew D

    2015-10-27

    Immune function is a costly line of defense against parasitism. When infected with a parasite, hosts frequently lose mass due to these costs. However, some infected hosts (e.g. highly resistant individuals) can clear infections with seemingly little fitness losses, but few studies have tested how resistant hosts mitigate these costly immune defenses. We explored this topic using eastern red-backed salamanders Plethodon cinereus and the fungal pathogen Batrachochytrium dendrobatidis (Bd). Bd is generally lethal for amphibians, and stereotypical symptoms of infection include loss in mass and deficits in feeding. However, individuals of P. cinereus can clear their Bd infections with seemingly few fitness costs. We conducted an experiment in which we repeatedly observed the feeding activity of Bd-infected and non-infected salamanders. We found that Bd-infected salamanders generally increased their feeding activity compared to non-infected salamanders. The fact that we did not observe any differences in mass change between the treatments suggests that increased feeding might help Bd-infected salamanders minimize the costs of an effective immune response. PMID:26503775

  9. Infection of goats with goatpox virus triggers host antiviral defense through activation of innate immune signaling.

    PubMed

    Zeng, Xiancheng; Wang, Song; Chi, Xiaojuan; Chen, Shi-long; Huang, Shile; Lin, Qunqun; Xie, Baogui; Chen, Ji-Long

    2016-02-01

    Goatpox, caused by goatpox virus (GTPV), is one of the most serious infectious diseases associated with high morbidity and mortality in goats. However, little is known about involvement of host innate immunity during the GTPV infection. For this, goats were experimentally infected with GTPV. The results showed that GTPV infection significantly induced mRNA expression of type I interferon (IFN)-α and IFN-β in peripheral blood lymphocytes, spleen and lung. In addition, GTPV infection enhanced expression of several inflammatory cytokines, including interleukin (IL)-1β, IL-6, IL-18; and tumor necrosis factor-α (TNF-α). Strikingly, infection with GTPV activated signal transducers and activators of transcription 3 (STAT3), a critical cytokine signaling molecule. Interestingly, the virus infection induced expression of suppressor of cytokine signaling (SOCS)-1. Importantly, the infection resulted in an increased expression of some critical interferon-stimulated genes, such as interferon-induced transmembrane protein (IFITM) 1, IFITM3, interferon stimulated gene (ISG) 15 and ISG20. Furthermore, we found that infection with GTPV up-regulated expression of Toll-like receptor (TLR) 2 and TLR9. These results revealed that GTPV infection activated host innate immune signaling and thereby triggered antiviral innate immunity. The findings provide novel insights into complex mechanisms underlying GTPV-host interaction and pathogenesis of GTPV. PMID:26850535

  10. Tetherin/BST-2 promotes dendritic cell activation and function during acute retrovirus infection

    PubMed Central

    Li, Sam X.; Barrett, Bradley S.; Guo, Kejun; Kassiotis, George; Hasenkrug, Kim J.; Dittmer, Ulf; Gibbert, Kathrin; Santiago, Mario L.

    2016-01-01

    Tetherin/BST-2 is a host restriction factor that inhibits retrovirus release from infected cells in vitro by tethering nascent virions to the plasma membrane. However, contradictory data exists on whether Tetherin inhibits acute retrovirus infection in vivo. Previously, we reported that Tetherin-mediated inhibition of Friend retrovirus (FV) replication at 2 weeks post-infection correlated with stronger natural killer, CD4+ T and CD8+ T cell responses. Here, we further investigated the role of Tetherin in counteracting retrovirus replication in vivo. FV infection levels were similar between wild-type (WT) and Tetherin KO mice at 3 to 7 days post-infection despite removal of a potent restriction factor, Apobec3/Rfv3. However, during this phase of acute infection, Tetherin enhanced myeloid dendritic cell (DC) function. DCs from infected, but not uninfected, WT mice expressed significantly higher MHC class II and the co-stimulatory molecule CD80 compared to Tetherin KO DCs. Tetherin-associated DC activation during acute FV infection correlated with stronger NK cell responses. Furthermore, Tetherin+ DCs from FV-infected mice more strongly stimulated FV-specific CD4+ T cells ex vivo compared to Tetherin KO DCs. The results link the antiretroviral and immunomodulatory activity of Tetherin in vivo to improved DC activation and MHC class II antigen presentation. PMID:26846717

  11. Infection.

    PubMed

    Saigal, Gaurav; Nagornaya, Natalya; Post, M Judith D

    2016-01-01

    Imaging is useful in the diagnosis and management of infections of the central nervous system. Typically, imaging findings at the outset of the disease are subtle and nonspecific, but they often evolve to more definite imaging patterns in a few days, with less rapidity than for stroke but faster than for neoplastic lesions. This timing is similar to that of noninfectious inflammatory brain disease, such as multiple sclerosis. Fortunately, imaging patterns help to distinguish the two kinds of processes. Other than for sarcoidosis, the meninges are seldom involved in noninfectious inflammation; in contrast, many infectious processes involve the meninges, which then enhance with contrast on computed tomography (CT) or magnetic resonance imaging (MRI). However, brain infection causes a vast array of imaging patterns. Although CT is useful when hemorrhage or calcification is suspected or bony detail needs to be determined, MRI is the imaging modality of choice in the investigation of intracranial infections. Imaging sequences such as diffusion-weighted imaging help in accurately depicting the location and characterizing pyogenic infections and are particularly useful in differentiating bacterial infections from other etiologies. Susceptibility-weighted imaging is extremely useful for the detection of hemorrhage. Although MR spectroscopy findings can frequently be nonspecific, certain conditions such as bacterial abscesses show a relatively specific spectral pattern and are useful in diagnosing and constituting immediate therapy. In this chapter we review first the imaging patterns associated with involvement of various brain structures, such as the epidural and subdural spaces, the meninges, the brain parenchyma, and the ventricles. Involvement of these regions is illustrated with bacterial infections. Next we illustrate the patterns associated with viral and prion diseases, followed by mycobacterial and fungal infections, to conclude with a review of imaging findings

  12. Using Essential Biodiversity Variables (EBVs) As a Framework for Coordination Between Research and Monitoring Networks: A Case Study with Phenology

    NASA Astrophysics Data System (ADS)

    Weltzin, J. F.; Jones, K. D.; Brown, J. F.; Elmendorf, S.; Enquist, C.; Rosemartin, A.; Thorpe, A.; Wee, B.

    2014-12-01

    The United Nations Convention on Biological Diversity (CBD) was organized to encourage countries to take action to address issues of declining biodiversity. In2010, the CBD identified specific goals for 2011-2020 (the "Aichi Targets") and a tiered system of indicators necessary to achieve those targets. Essential biodiversity variables (EBVs) are the standardized measurements and observations at the base of this system; they are the basic level of information that is necessary to calculate these indicators. By providing a list of pre-defined EBVs, existing research and research planned for the future can align measurements to address common questions. We assessed the applicability of phenology EBVs for standardizing measurements across observation networks within the US as a test case for use of the standardized used of EBVs. Phenology products from the USA National Phenology Network, a citizen science observer based program, NEON, a multi-scale ecological observatory, and remotely sensed data from USGS EROS were considered for this purpose. Essential Biodiversity Variables currently defined for phenology are insufficient to support consistent measurement across monitoring networks. Specifically, phenology which is a field of study, is currently listed as a single EBV within the general category of 'species traits'. With the only guidance provided to future observation networks being that of measuring 'phenology,' there would likely be as many approaches to achieving this goal as networks participating. We propose more narrowly defined variables which may be more appropriate for standardization and demonstrate how these measurements satisfy the basic characteristics of an EBV in that they are relevant, sensitive to change, biological and generalizable, scalable, feasible, stable and, represent state variables. We map these variables to the tiered indicators identified by the CBD and, finally, to Aichi Targets to which they contribute. EBVs may be used not only to

  13. Genital ulcers as initial manifestation of Epstein-Barr virus infection: two new cases and a review of the literature.

    PubMed

    Halvorsen, Jon Anders; Brevig, Trine; Aas, Torkild; Skar, Anne Grete; Slevolden, Ellen Margrethe; Moi, Harald

    2006-01-01

    Genital ulceration is an uncommon manifestation of primary Epstein-Barr virus (EBV) infection. We present here two cases of genital ulcers probably caused by EBV. The first case is a 12-year-old girl with a genital ulcer appearing before specific EBV serology could identify a primary infection. However, serology was positive 13 days after the ulcer appeared. Polymerase chain reaction for EBV was positive in the biopsy from the ulcer as well. The second case is an 18-year-old female in whom the specific EBV serology was positive 8 days after appearance of the ulcer. The ulcers in both cases healed after 21 days. We reviewed the literature and a total of 26 cases of EBV-associated genital ulcers in females are now published. Median age of the 26 cases is 14.5 years of whom only 6 reports previous sexual contact. Mean healing time for the ulcers is 18 days. Our two cases correspond well with clinical reports of 24 EBV-associated genital ulcers in the literature.

  14. Activation of Hypoxia Inducible Factor 1 Is a General Phenomenon in Infections with Human Pathogens

    PubMed Central

    Werth, Nadine; Beerlage, Christiane; Rosenberger, Christian; Yazdi, Amir S.; Edelmann, Markus; Amr, Amro; Bernhardt, Wanja; von Eiff, Christof; Becker, Karsten; Schäfer, Andrea; Peschel, Andreas; Kempf, Volkhard A. J.

    2010-01-01

    Background Hypoxia inducible factor (HIF)-1 is the key transcriptional factor involved in the adaptation process of cells and organisms to hypoxia. Recent findings suggest that HIF-1 plays also a crucial role in inflammatory and infectious diseases. Methodology/Principal Findings Using patient skin biopsies, cell culture and murine infection models, HIF-1 activation was determined by immunohistochemistry, immunoblotting and reporter gene assays and was linked to cellular oxygen consumption. The course of a S. aureus peritonitis was determined upon pharmacological HIF-1 inhibition. Activation of HIF-1 was detectable (i) in all ex vivo in biopsies of patients suffering from skin infections, (ii) in vitro using cell culture infection models and (iii) in vivo using murine intravenous and peritoneal S. aureus infection models. HIF-1 activation by human pathogens was induced by oxygen-dependent mechanisms. Small colony variants (SCVs) of S. aureus known to cause chronic infections did not result in cellular hypoxia nor in HIF-1 activation. Pharmaceutical inhibition of HIF-1 activation resulted in increased survival rates of mice suffering from a S. aureus peritonitis. Conclusions/Significance Activation of HIF-1 is a general phenomenon in infections with human pathogenic bacteria, viruses, fungi and protozoa. HIF-1-regulated pathways might be an attractive target to modulate the course of life-threatening infections. PMID:20644645

  15. NK Cell Influence on the Outcome of Primary Epstein-Barr Virus Infection.

    PubMed

    Chijioke, Obinna; Landtwing, Vanessa; Münz, Christian

    2016-01-01

    The herpesvirus Epstein-Barr virus (EBV) was discovered as the first human candidate tumor virus in Burkitt's lymphoma more than 50 years ago. Despite its strong growth transforming capacity, more than 90% of the human adult population carries this virus asymptomatically under near perfect immune control. The mode of primary EBV infection is in part responsible for EBV-associated diseases, including Hodgkin's lymphoma. It is, therefore, important to understand which circumstances lead to symptomatic primary EBV infection, called infectious mononucleosis (IM). Innate immune control of lytic viral replication by early-differentiated natural killer (NK) cells was found to attenuate IM symptoms and continuous loss of the respective NK cell subset during the first decade of life might predispose for IM during adolescence. In this review, we discuss the evidence that NK cells are involved in the immune control of EBV, mechanisms by which they might detect and control lytic EBV replication, and compare NK cell subpopulations that expand during different human herpesvirus infections. PMID:27621731

  16. NK Cell Influence on the Outcome of Primary Epstein–Barr Virus Infection

    PubMed Central

    Chijioke, Obinna; Landtwing, Vanessa; Münz, Christian

    2016-01-01

    The herpesvirus Epstein–Barr virus (EBV) was discovered as the first human candidate tumor virus in Burkitt’s lymphoma more than 50 years ago. Despite its strong growth transforming capacity, more than 90% of the human adult population carries this virus asymptomatically under near perfect immune control. The mode of primary EBV infection is in part responsible for EBV-associated diseases, including Hodgkin’s lymphoma. It is, therefore, important to understand which circumstances lead to symptomatic primary EBV infection, called infectious mononucleosis (IM). Innate immune control of lytic viral replication by early-differentiated natural killer (NK) cells was found to attenuate IM symptoms and continuous loss of the respective NK cell subset during the first decade of life might predispose for IM during adolescence. In this review, we discuss the evidence that NK cells are involved in the immune control of EBV, mechanisms by which they might detect and control lytic EBV replication, and compare NK cell subpopulations that expand during different human herpesvirus infections. PMID:27621731

  17. NK Cell Influence on the Outcome of Primary Epstein–Barr Virus Infection

    PubMed Central

    Chijioke, Obinna; Landtwing, Vanessa; Münz, Christian

    2016-01-01

    The herpesvirus Epstein–Barr virus (EBV) was discovered as the first human candidate tumor virus in Burkitt’s lymphoma more than 50 years ago. Despite its strong growth transforming capacity, more than 90% of the human adult population carries this virus asymptomatically under near perfect immune control. The mode of primary EBV infection is in part responsible for EBV-associated diseases, including Hodgkin’s lymphoma. It is, therefore, important to understand which circumstances lead to symptomatic primary EBV infection, called infectious mononucleosis (IM). Innate immune control of lytic viral replication by early-differentiated natural killer (NK) cells was found to attenuate IM symptoms and continuous loss of the respective NK cell subset during the first decade of life might predispose for IM during adolescence. In this review, we discuss the evidence that NK cells are involved in the immune control of EBV, mechanisms by which they might detect and control lytic EBV replication, and compare NK cell subpopulations that expand during different human herpesvirus infections.

  18. Group B Streptococcal Infection and Activation of Human Astrocytes

    PubMed Central

    Stoner, Terri D.; Weston, Thomas A.; Trejo, JoAnn; Doran, Kelly S.

    2015-01-01

    Background Streptococcus agalactiae (Group B Streptococcus, GBS) is the leading cause of life-threatening meningitis in human newborns in industrialized countries. Meningitis results from neonatal infection that occurs when GBS leaves the bloodstream (bacteremia), crosses the blood-brain barrier (BBB), and enters the central nervous system (CNS), where the bacteria contact the meninges. Although GBS is known to invade the BBB, subsequent interaction with astrocytes that physically associate with brain endothelium has not been well studied. Methodology/Principal Findings We hypothesize that human astrocytes play a unique role in GBS infection and contribute to the development of meningitis. To address this, we used a well- characterized human fetal astrocyte cell line, SVG-A, and examined GBS infection in vitro. We observed that all GBS strains of representative clinically dominant serotypes (Ia, Ib, III, and V) were able to adhere to and invade astrocytes. Cellular invasion was dependent on host actin cytoskeleton rearrangements, and was specific to GBS as Streptococcus gordonii failed to enter astrocytes. Analysis of isogenic mutant GBS strains deficient in various cell surface organelles showed that anchored LTA, serine-rich repeat protein (Srr1) and fibronectin binding (SfbA) proteins all contribute to host cell internalization. Wild-type GBS also displayed an ability to persist and survive within an intracellular compartment for at least 12 h following invasion. Moreover, GBS infection resulted in increased astrocyte transcription of interleukin (IL)-1β, IL-6 and VEGF. Conclusions/Significance This study has further characterized the interaction of GBS with human astrocytes, and has identified the importance of specific virulence factors in these interactions. Understanding the role of astrocytes during GBS infection will provide important information regarding BBB disruption and the development of neonatal meningitis. PMID:26030618

  19. Establishment and operation of a Good Manufacturing Practice-compliant allogeneic Epstein-Barr virus (EBV)-specific cytotoxic cell bank for the treatment of EBV-associated lymphoproliferative disease.

    PubMed

    Vickers, Mark A; Wilkie, Gwen M; Robinson, Nicolas; Rivera, Nadja; Haque, Tanzina; Crawford, Dorothy H; Barry, Jacqueline; Fraser, Neil; Turner, David M; Robertson, Victoria; Dyer, Phil; Flanagan, Peter; Newlands, Helen R; Campbell, John; Turner, Marc L

    2014-11-01

    Epstein-Barr virus (EBV) is associated with several malignancies, including post-transplant lymphoproliferative disorder (PTLD). Conventional treatments for PTLD are often successful, but risk organ rejection and cause significant side effects. EBV-specific cytotoxic T lymphocytes (CTLs) generated in vitro from peripheral blood lymphocytes provide an alternative treatment modality with few side effects, but autologous CTLs are difficult to use in clinical practice. Here we report the establishment and operation of a bank of EBV-specific CTLs derived from 25 blood donors with human leucocyte antigen (HLA) types found at high frequency in European populations. Since licensure, there have been enquiries about 37 patients, who shared a median of three class I and two class II HLA types with these donors. Cells have been infused into ten patients with lymphoproliferative disease, eight of whom achieved complete remission. Neither patient with refractory disease was matched for HLA class II. Both cases of EBV-associated non-haematopoietic sarcoma receiving cells failed to achieve complete remission. Thirteen patients died before any cells could be issued, emphasizing that the bank should be contacted before patients become pre-terminal. Thus, this third party donor-derived EBV-specific CTL cell bank can supply most patients with appropriately matched cells and most recipients have good outcomes. PMID:25066775

  20. Establishment and operation of a Good Manufacturing Practice-compliant allogeneic Epstein-Barr virus (EBV)-specific cytotoxic cell bank for the treatment of EBV-associated lymphoproliferative disease.

    PubMed

    Vickers, Mark A; Wilkie, Gwen M; Robinson, Nicolas; Rivera, Nadja; Haque, Tanzina; Crawford, Dorothy H; Barry, Jacqueline; Fraser, Neil; Turner, David M; Robertson, Victoria; Dyer, Phil; Flanagan, Peter; Newlands, Helen R; Campbell, John; Turner, Marc L

    2014-11-01

    Epstein-Barr virus (EBV) is associated with several malignancies, including post-transplant lymphoproliferative disorder (PTLD). Conventional treatments for PTLD are often successful, but risk organ rejection and cause significant side effects. EBV-specific cytotoxic T lymphocytes (CTLs) generated in vitro from peripheral blood lymphocytes provide an alternative treatment modality with few side effects, but autologous CTLs are difficult to use in clinical practice. Here we report the establishment and operation of a bank of EBV-specific CTLs derived from 25 blood donors with human leucocyte antigen (HLA) types found at high frequency in European populations. Since licensure, there have been enquiries about 37 patients, who shared a median of three class I and two class II HLA types with these donors. Cells have been infused into ten patients with lymphoproliferative disease, eight of whom achieved complete remission. Neither patient with refractory disease was matched for HLA class II. Both cases of EBV-associated non-haematopoietic sarcoma receiving cells failed to achieve complete remission. Thirteen patients died before any cells could be issued, emphasizing that the bank should be contacted before patients become pre-terminal. Thus, this third party donor-derived EBV-specific CTL cell bank can supply most patients with appropriately matched cells and most recipients have good outcomes.

  1. PPARγ Is Activated during Congenital Cytomegalovirus Infection and Inhibits Neuronogenesis from Human Neural Stem Cells

    PubMed Central

    Rolland, Maude; Li, Xiaojun; Perez-Berezo, Teresa; Rauwel, Benjamin; Benchoua, Alexandra; Bessières, Bettina; Aziza, Jacqueline; Cenac, Nicolas; Luo, Minhua; Casper, Charlotte; Peschanski, Marc; Gonzalez-Dunia, Daniel; Leruez-Ville, Marianne; Davrinche, Christian; Chavanas, Stéphane

    2016-01-01

    Congenital infection by human cytomegalovirus (HCMV) is a leading cause of permanent sequelae of the central nervous system, including sensorineural deafness, cerebral palsies or devastating neurodevelopmental abnormalities (0.1% of all births). To gain insight on the impact of HCMV on neuronal development, we used both neural stem cells from human embryonic stem cells (NSC) and brain sections from infected fetuses and investigated the outcomes of infection on Peroxisome Proliferator-Activated Receptor gamma (PPARγ), a transcription factor critical in the developing brain. We observed that HCMV infection dramatically impaired the rate of neuronogenesis and strongly increased PPARγ levels and activity. Consistent with these findings, levels of 9-hydroxyoctadecadienoic acid (9-HODE), a known PPARγ agonist, were significantly increased in infected NSCs. Likewise, exposure of uninfected NSCs to 9-HODE recapitulated the effect of infection on PPARγ activity. It also increased the rate of cells expressing the IE antigen in HCMV-infected NSCs. Further, we demonstrated that (1) pharmacological activation of ectopically expressed PPARγ was sufficient to induce impaired neuronogenesis of uninfected NSCs, (2) treatment of uninfected NSCs with 9-HODE impaired NSC differentiation and (3) treatment of HCMV-infected NSCs with the PPARγ inhibitor T0070907 restored a normal rate of differentiation. The role of PPARγ in the disease phenotype was strongly supported by the immunodetection of nuclear PPARγ in brain germinative zones of congenitally infected fetuses (N = 20), but not in control samples. Altogether, our findings reveal a key role for PPARγ in neurogenesis and in the pathophysiology of HCMV congenital infection. They also pave the way to the identification of PPARγ gene targets in the infected brain. PMID:27078877

  2. Behçet's disease diagnosed after acute HIV infection: viral replication activating underlying autoimmunity?

    PubMed

    Roscoe, Clay; Kinney, Rebecca; Gilles, Ryan; Blue, Sky

    2015-05-01

    Behçet's disease is an autoimmune systemic vasculitis that can occur after exposure to infectious agents. Behçet's disease also has been associated with HIV infection, including de novo development of this condition during chronic HIV infection and resolution of Behçet's disease symptoms following initiation of antiretroviral therapy. We describe a patient who presented with systemic vasculitis with skin and mucous membrane ulcerations in the setting of acute HIV infection, who was eventually diagnosed with Behçet's disease, demonstrating a possible link between acute HIV infection, immune activation and development of autoimmunity.

  3. Activation of small ruminant aortic endothelial cells after in vitro infection by caprine arthritis encephalitis virus.

    PubMed

    Jan, C L; Greenland, T; Gounel, F; Balleydier, S; Mornex, J F

    2000-12-01

    Small ruminants infected by the lentiviruses caprine arthritis-encephalitis virus (CAEV), originally isolated from a goat, or maedi-visna virus, originally from sheep, typically develop an organising lymphoid infiltration of affected tissues. This could reflect modulation of the migration pattern of lymphocytes in infected animals. Possible active contribution by vascular endothelial cells was investigated using an in vitro model. Low-passage cultured ovine aortic endothelium proved susceptible to productive infection by CAEV without significant cytotoxicity. Infected endothelial cells maintained expression of endothelial markers, increased MHC class I antigen expression and initiated expression of the adhesion molecule VCAM -1 and, at a late stage, MHC class II antigens. Infected endothelial cells showed a two-fold increase in binding capacity for sheep peripheral blood leucocytes over uninfected controls. Such events could contribute to the tissue distribution of lymphoid cells and local immune responses in lentiviral infections of small ruminants. PMID:11124093

  4. Decline in HIV infectivity following the introduction of highly active antiretroviral therapy

    PubMed Central

    Porco, Travis C.; Martin, Jeffrey N.; Page-Shafer, Kimberly A.; Cheng, Amber; Charlebois, Edwin; Grant, Robert M.; Osmond, Dennis H.

    2008-01-01

    Objective Little is known about the degree to which widespread use of antiretroviral therapy in a community reduces uninfected individuals’ risk of acquiring HIV. We estimated the degree to which the probability of HIV infection from an infected partner (the infectivity) declined following the introduction of highly active antiretroviral therapy (HAART) in San Francisco. Design Homosexual men from the San Francisco Young Men’s Health Study, who were initially uninfected with HIV, were asked about sexual practices, and tested for HIV antibodies at each of four follow-up visits during a 6-year period spanning the advent of widespread use of HAART (1994 to 1999). Methods We estimated the infectivity of HIV (per-partnership probability of transmission from an infected partner) using a probabilistic risk model based on observed incident infections and self-reported sexual risk behavior, and tested the hypothesis that infectivity was the same before and after HAART was introduced. Results A total of 534 homosexual men were evaluated. Decreasing trends in HIV seroincidence were observed despite increases in reported number of unprotected receptive anal intercourse partners. Conservatively assuming a constant prevalence of HIV infection between 1994 and 1999, HIV infectivity decreased from 0.120 prior to widespread use of HAART, to 0.048 after the widespread use of HAART – a decline of 60% (P = 0.028). Conclusions Use of HAART by infected persons in a community appears to reduce their infectiousness and therefore may provide an important HIV prevention tool. PMID:15090833

  5. Correlation between DNA methyltransferases expression and Epstein-Barr virus, JC polyomavirus and Helicobacter pylori infections in gastric carcinomas.

    PubMed

    Ksiaa, F; Ziadi, S; Gacem, R B; Dhiab, M B; Trimeche, M

    2014-01-01

    It' is accepted that aberrant expression of DNA methyltransferases (DNMTs) is responsible for hypermethylation in genes. However, there are limited data related to factors inducing aberrant expression of DNMTs. A total of 43 surgically resected gastrc carcinomas (GC) samples were analysed. Using immunohistochemistry assay we have determined expression level of DNMT1 and 3b. The presence of H.pylori was evaluated by histology, whereas JC polyomavirus (JCV) and Epstein-Barr virus (EBV) detection were carried out by PCR and in situ hybridization techniques, respectively. High expression of DNMT1 and 3b were detected in 46.5% and 53.5% of GC cases, respectively. Co-expression of DNMT1 and 3b were found in 37.2% of cases. Using different techniques, H. pylori, JCV and EBV were detected in 55.8%, 32.6% and 9%, respectively. Moreover, in 37% of cases, we noted the presence of JCV and/or EBV infections. H.pylori co-infection was found in 64.3% (9/14) of JCV positive cases and in 50% of EBV positive GC, without a reliable significant relationship. Correlation analyses have showed a marked increase in DNMT1 expression in EBV associated GC (P= 0.02). Also, co-expression of DNMT1 and 3b was significantly associated with EBV infection in GC (P=0.05). Similarly, JCV associated GC mostly displayed DNMT1 positive status, but the difference did not reach the significant threshold. Nevertheless, infection with JCV and/or EBV was significantly correlated with increased expression of DNMT1 in GC (P= 0.05). Our study suggests that EBV and JCV infections in GC correlated with deregulation of DNA methyltransferases. PMID:25341997

  6. From Wasting to Obesity: The Contribution of Nutritional Status to Immune Activation in HIV Infection.

    PubMed

    Koethe, John R; Heimburger, Douglas C; PrayGod, George; Filteau, Suzanne

    2016-10-01

    The impact of human immunodeficiency virus (HIV) infection on innate and adaptive immune activation occurs in the context of host factors, which serve to augment or dampen the physiologic response to the virus. Independent of HIV infection, nutritional status, particularly body composition, affects innate immune activation through a variety of conditions, including reduced mucosal barrier defenses and microbiome dysbiosis in malnutrition and the proinflammatory contribution of adipocytes and stromal vascular cells in obesity. Similarly, T-cell activation, proliferation, and cytokine expression are reduced in the setting of malnutrition and increased in obesity, potentially due to adipokine regulatory mechanisms restraining energy-avid adaptive immunity in times of starvation and exerting a paradoxical effect in overnutrition. The response to HIV infection is situated within these complex interactions between host nutritional health and immunologic function, which contribute to the varied phenotypes of immune activation among HIV-infected patients across a spectrum from malnutrition to obesity.

  7. From Wasting to Obesity: The Contribution of Nutritional Status to Immune Activation in HIV Infection.

    PubMed

    Koethe, John R; Heimburger, Douglas C; PrayGod, George; Filteau, Suzanne

    2016-10-01

    The impact of human immunodeficiency virus (HIV) infection on innate and adaptive immune activation occurs in the context of host factors, which serve to augment or dampen the physiologic response to the virus. Independent of HIV infection, nutritional status, particularly body composition, affects innate immune activation through a variety of conditions, including reduced mucosal barrier defenses and microbiome dysbiosis in malnutrition and the proinflammatory contribution of adipocytes and stromal vascular cells in obesity. Similarly, T-cell activation, proliferation, and cytokine expression are reduced in the setting of malnutrition and increased in obesity, potentially due to adipokine regulatory mechanisms restraining energy-avid adaptive immunity in times of starvation and exerting a paradoxical effect in overnutrition. The response to HIV infection is situated within these complex interactions between host nutritional health and immunologic function, which contribute to the varied phenotypes of immune activation among HIV-infected patients across a spectrum from malnutrition to obesity. PMID:27625434

  8. Effects of malaria (Plasmodium relicturm) on activity budgets of experimentally-infected juvenile Apapane (Himatione sanquinea)

    USGS Publications Warehouse

    Yorinks, N.; Atkinson, C.T.

    2000-01-01

    We used behavioral, physiological, and parasitological measures to document effects of acute malarial infections on activity budgets of experimentally infected juvenile Apapane (Himatione sanguinea). Five of eight birds died within 20 to 32 days after exposure to a single infective mosquito bite. Infected Apapane devoted less time to locomotory activities involving flight, walking or hopping, and stationary activities such as singing, preening, feeding, and probing. The amount of time spent sitting was positively correlated with parasitemia and increased dramatically after infection and between treatment and control groups. Birds that succumbed to infection experienced a significant loss of body mass and subcutaneous fat, whereas surviving Apapane were better able to maintain body condition and fat levels. When rechallenged with the parasite five months after initial infection, surviving birds experienced no increase in parasitemia, indicating that they had become immune to reinfection. Regardless of the outcome, infected birds experienced acute illness that would have left them unable to forage or to escape from predators in the wild.

  9. Cell surface phenotyping and cytokine production of Epstein-Barr Virus (EBV)-transformed lymphoblastoid cell lines (LCLs).

    PubMed

    Wroblewski, Joanne M; Copple, Angela; Batson, Lydia P; Landers, Cheri D; Yannelli, John R

    2002-06-01

    Epstein-Barr Virus-transformed B lymphoblastoid cell lines (EBV-LCLs) are routinely used for the in vitro expansion of T cells. However, these cell lines are reported to produce the cytokine IL-10, which is inhibitory for T cells. We, therefore, characterized a panel of 37 EBV-LCLs for a variety of cell surface markers, for secretion of various cytokines including IL-10 and for immunoglobulin production. These cell lines were derived from normal donors or patients with nonsmall cell lung cancer, acute myelogenous leukemia, melanoma or colon cancer. Overall, 26 lines were positive for CD19 and CD20, and 11 were negative for both. All of the lines were strongly HLA-DR+, while CD40 expression was variable. Twenty-four (65%) were both CD23+ and secreted immunoglobulin, and 33 expressed kappa and/or lambda light chains. Additionally, all of the EBV-LCLs were negative for T cell (CD3), NK cell (CD16, CD56), monocyte (CD14) and granulocyte (CD66b) surface markers. Some level of IL-10, IL-6, IL-12p40 and TNF-alpha cytokine production was detected in 33, 18, 19 and 12 EBV-LCLs, respectively. Together, these data reflect the heterogeneity of EBV-LCLs, which cautions their use nondiscriminately in various immunologic assays.

  10. EBV+ cutaneous B-cell lymphoproliferation of the leg in an elderly patient with mycosis fungoides and methotrexate treatment.

    PubMed

    Rausch, Thierry; Cairoli, Anne; Benhattar, Jean; Spring, Philipp; Hohl, Daniel; de Leval, Laurence

    2013-01-01

    A 77-year-old man with a 5-year history of mycosis fungoides (MF) who had received several lines of therapy, including intravenous courses of Methotrexate (MTX) for the past 2 years, went on to develop several ulcerated cutaneous nodules on the left leg. Biopsy revealed diffuse sheets of EBV-positive large B cells (CD20+ CD30 ± IgM Lambda), with an angiocentric distribution and a monoclonal IGH gene rearrangement. Although the pathological features were diagnostic for an EBV-positive diffuse large B-cell lymphoma (DLBCL), several possibilities could be considered for assignment to a specific entity: EBV-positive DLBCL of the elderly, methotrexate-induced lymphoproliferative disorder (LPD), lymphomatoid granulomatosis, or the more recently described EBV-positive mucocutaneous ulcer. The development of EBV+ lymphoproliferations has been reported in two other patients with MF under MTX, and occurred as skin lesions of the leg in one of these and in the current case, which may question the relatedness to primary cutaneous DLCBL, leg-type. PMID:23031074

  11. The Relationship between Active Trachoma and Ocular Chlamydia trachomatis Infection before and after Mass Antibiotic Treatment

    PubMed Central

    Ramadhani, Athumani M.; Derrick, Tamsyn; Macleod, David; Holland, Martin J.; Burton, Matthew J.

    2016-01-01

    Background Trachoma is a blinding disease, initiated in early childhood by repeated conjunctival infection with the obligate intracellular bacterium Chlamydia trachomatis. The population prevalence of the clinical signs of active trachoma; ‘‘follicular conjunctivitis” (TF) and/or ‘‘intense papillary inflammation” (TI), guide programmatic decisions regarding the initiation and cessation of mass drug administration (MDA). However, the persistence of TF following resolution of infection at both the individual and population level raises concerns over the suitability of this clinical sign as a marker for C. trachomatis infection. Methodology/Principle Findings We systematically reviewed the literature for population-based studies and those including randomly selected individuals, which reported the prevalence of the clinical signs of active trachoma and ocular C. trachomatis infection by nucleic acid amplification test. We performed a meta-analysis to assess the relationship between active trachoma and C. trachomatis infection before and after MDA. TF and C. trachomatis infection were strongly correlated prior to MDA (r = 0.92, 95%CI 0.83 to 0.96, p<0.0001); the relationship was similar when the analysis was limited to children. A moderate correlation was found between TI and prevalence of infection. Following MDA, the relationship between TF and infection prevalence was weaker (r = 0.60, 95%CI 0.25 to 0.81, p = 0.003) and there was no correlation between TI and C. trachomatis infection. Conclusions/Significance Prior to MDA, TF is a good indicator of the community prevalence of C. trachomatis infection. Following MDA, the prevalence of TF tends to overestimate the underlying infection prevalence. In order to prevent unnecessary additional rounds of MDA and to accurately ascertain when elimination goals have been reached, a cost-effective test for C. trachomatis that can be administered in low-resource settings remains desirable. PMID:27783678

  12. Houttuynia cordata blocks HSV infection through inhibition of NF-κB activation.

    PubMed

    Chen, Xiaoqing; Wang, Zhongxia; Yang, Ziying; Wang, Jingjing; Xu, Yunxia; Tan, Ren-Xiang; Li, Erguang

    2011-11-01

    Houttuynia cordata Thunb. is a medicinal plant widely used in folk medicine in several Asian countries. It has been reported that a water extract of H. cordata exhibits activity against herpes simplex virus (HSV) and the virus of severe acute respiratory syndrome (SARS), although the mechanisms are not fully understood yet. Previous studies have demonstrated absolute requirement of NF-κB activation for efficient replication of HSV-1 and HSV-2 and inhibition of NF-κB activation has been shown to suppress HSV infection. Here we show that a hot water extract of H. cordata (HCWE) inhibits HSV-2 infection through inhibition of NF-κB activation. The IC(50) was estimated at 50 μg/ml of lyophilized HCWE powder. At 150 and 450 μg/ml, HCWE blocked infectious HSV-2 production by more than 3 and 4 logs, respectively. The inhibitory activity was concomitant with an inhibition of NF-κB activation by HSV-2 infection. Although activation of NF-κB and Erk MAPK has been implicated for HSV replication and growth, HCWE showed no effect on HSV-2-induced Erk activation. Furthermore, we show that treatment with quercetin, quercitrin or isoquercitrin, major water extractable flavonoids from H. cordata, significantly blocked HSV-2 infection. These results together demonstrated that H. cordata blocks HSV-2 infection through inhibition of NF-κB activation. PMID:21951655

  13. Anti-infection activity of nanostructured titanium percutaneous implants with a postoperative infection model

    NASA Astrophysics Data System (ADS)

    Tan, Jing; Li, Yiting; Liu, Zhiyuan; Qu, Shuxin; Lu, Xiong; Wang, Jianxin; Duan, Ke; Weng, Jie; Feng, Bo

    2015-07-01

    The titanium percutaneous implants were widely used in clinic; however, they have an increased risk of infection since they breach the skin barrier. Lack of complete skin integration with the implants can cause infection and implant removal. In this work, three titania nanotubes (TNT) with different diameters, 50 nm (TNT-50), 100 nm (TNT-100) and 150 nm (TNT-150) arrays were prepared on titanium surfaces by anodization, pure titanium (pTi) was used as control. Samples were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle analysis. The antibacterial efficiency of TNT was evaluated in vitro against Staphylococcus aureus under the visible light. The results indicated that TNT-100 had the highest antibacterial efficiency under the visible light. Subsequently, TNT implants and pTi implants were placed subcutaneously to the dorsum of New Zealand White rabbits, 108 CFU S. aureus was inoculated into the implant sites 4 h after surgery. The TNF-alpha and IL-1alpha were determined using enzyme linked immunoassay (ELISA). TNT implants revealed less inflammatory factor release than pTi implants with or without injected S. aureus liquid. According to the histological results, the TNT implants displayed excellent tissue integration. Whereas, pTi implants were surrounded with fibrotic capsule, and the skin tissue was almost separated from the implant surface. Therefore, the TNT significantly inhibited the infection risk and enhanced tissue integration of the percutaneous implants compared to pTi. The immersion test in the culture medium suggested that one of causes be probably more proteins adsorbed on TNT than on pTi.

  14. Peripheral T-cell lymphomas of follicular T-helper cell derivation with Hodgkin/Reed-Sternberg cells of B-cell lineage: Both EBV-positive and EBV-negative variants exist

    PubMed Central

    Nicolae, Alina; Pittaluga, Stefania; Venkataraman, Girish; Vijnovich-Baron, Anahi; Xi, Liqiang; Raffeld, Mark; Jaffe, Elaine S.

    2012-01-01

    Peripheral T-cell lymphomas (PTCL) are functionally and morphologically complex. EBV-positive B- cells have been reported in angioimmunoblastic T-cell lymphoma (AITL) and other PTCL and may mimic Hodgkin/Reed-Sternberg (HRS) cells, but EBV-negative HRS-like B-cells have not been described. We wished to assess the nature of the PTCL associated with HRS-like cells, and to determine whether EBV-negative HRS-like cells may be seen. We identified 57 PTCL cases reported as containing HRS-like cells. These included 32 AITL, 19 PTCL-NOS, 3 PTCL-NOS, follicular variant, 1 PTCL-NOS, T-zone variant and 2 adult T-cell leukemia/lymphoma (ATLL). All patients were adults, median age, 63, and presented with lymphadenopathy. The male: female ratio was 31:26 (1.2:1). Clonal TRG rearrangement was detected in 46/53 cases. 6/38 cases had a concomitant clonal immunoglobulin gene rearrangement. In 52/57 cases the HRS cells were positive for EBV. Five cases, three classified as AITL and two as PTCL-NOS, follicular variant, contained HRS-like cells negative for EBV. All PTCL with EBV-negative HRS cells had a TFH-immunophenotype. The neoplastic T-cells expressed CD3, CD4, and PD-1, and formed rosettes around the HRS-like cells. The HRS-like cells were positive for CD20 (variable intensity), PAX5, CD30 and CD15 (4/5). We conclude that both EBV positive and EBV negative HRS-like B-cells may occur in the background of PTCL; caution is needed to avoid misdiagnosis as CHL. The close interaction between the HRS-like cells and the rosetting PD-1-positive T-cells suggests a possible pathogenetic role in this phenomenon, and provides new insights into the abnormal B-cell proliferations that occur in the context of TFH malignancies. PMID:23598959

  15. Hemolytic activity of plasma and urine from rabbits experimentally infected with Legionella pneumophila.

    PubMed

    Baine, W B; Rasheed, J K; Maca, H W; Kaufmann, A F

    1979-01-01

    Rabbits were infected with Legionella pneumophila by intravenous administration of allantoic fluid from eggs infected with this organism. Heated plasma from animals with severe illness caused by L. pneumophila lysed erythrocytes from guinea pigs in a radial hemolysis assay. Plasma from control rabbits did not lyse guinea pig erythrocytes in parallel assays. Urine from two of the infected animals also showed hemolytic activity. Attempts to induce illness in rabbits by intranasal administration of L. pneumohpila were less successful. Allantoic fluid from embrynated hen eggs developed hemolytic activity when maintained eithr in vitro at room temperature or in eggs whose embryos were killed by refrigeration. Hemolytic activity in filtrates of allantoic fluid from eggs infected with L. pneumophila, as previously reported, may not be due to the presence of bacterial hemolysins in the fluid. PMID:399383

  16. Bacterial skin infections, active component, U.S. Armed Forces, 2000-2012.

    PubMed

    2013-12-01

    From 2000 through 2012, health care records of the Military Health System documented 998,671 incident cases of bacterial skin infections among active component members of the U.S. Armed Forces. Most cases (97.3%) were identified from records of outpatient medical encounters rather than hospitalizations. Cellulitis accounted for half (50.9%) of all cases of bacterial skin infection but 96 percent of associated hospital bed days. Of all cases, 42.3 percent were "other" skin infections (i.e., folliculitis, impetigo, pyoderma, pyogenic granuloma, other and unspecified infections). The remainder were attributable to carbuncles/furuncles (6.6%) and erysipelas (0.1%). Rates of infection were higher among female service members except for "other" skin infections. In general, the highest rates were associated with youth, recruit trainee status, and junior enlisted rank; however, rates of erysipelas were highest among those 50 years and older. Annual incidence rates of all bacterial skin infections have increased greatly since 2000. During the entire period, such infections required more than 1.4 million health care encounters and 94,000 hospital bed-days (equivalent to 257 years of lost duty time). The prevention, early diagnosis, and treatment of bacterial skin infections, particularly in high risk settings, deserve continued emphasis. PMID:24428536

  17. Survival features of EBV-stabilized cells from centenarians: morpho-functional and transcriptomic analyses.

    PubMed

    Matarrese, Paola; Tinari, Antonella; Ascione, Barbara; Gambardella, Lucrezia; Remondini, Daniel; Salvioli, Stefano; Tenedini, Elena; Tagliafico, Enrico; Franceschi, Claudio; Malorni, Walter

    2012-12-01

    In the present work, we analyzed the survival features of six different Epstein-Barr virus (EBV)-stabilized lymphoid cell lines obtained from adult subjects and from subjects of more than 95 years. For the first, we found that lymphoid B cells from centenarians were more resistant to apoptosis induction and displayed a more developed lysosomal compartment, the most critical component of phagic machinery, in comparison with lymphoid B cells from adult subjects. In addition, cells from centenarians were capable of engulfing and digesting other cells, i.e., their siblings (even entire cells), whereas lymphoid cells from "control samples", i.e., from adults, did not. This behavior was improved by nutrient deprivation but, strikingly, it was unaffected by the autophagy-modulating drug, rapamycin, an autophagy inducer, and 3-methyladenine, an autophagy inhibitor. Transcriptomic analyses indicated that: (1) aspartyl proteases, (2) cell surface molecules such as integrins and cadherins, and (3) some components of cytoskeletal network could contribute to establish this survival phenotype. Also, Kyoto Encyclopedia of Genes and Genomes pathways such as Wnt signaling pathway, an essential contributor to cell migration and actin cytoskeleton remodeling, appeared as prominent. Although we cannot rule out the possibility that EBV-immortalization could play a role, since we observed this phagic behavior in cells from centenarians but not in those from adults, we hypothesize that it may represent an important survival determinant in cells from centenarians.

  18. The activation of p38MAPK and JNK pathways in bovine herpesvirus 1 infected MDBK cells.

    PubMed

    Zhu, Liqian; Yuan, Chen; Huang, Liyuan; Ding, Xiuyan; Wang, Jianye; Zhang, Dong; Zhu, Guoqiang

    2016-01-01

    We have shown previously that BHV-1 infection activates Erk1/2 signaling. Here, we show that BHV-1 provoked an early-stage transient and late-stage sustained activation of JNK, p38MAPK and c-Jun signaling in MDBK cells. C-Jun phosphorylation was dependent on JNK. These early events were partially due to the viral entry process. Unexpectedly, reactive oxygen species were not involved in the later activation phase. Interestingly, only activated JNK facilitated the viral multiplication identified through both chemical inhibitor and siRNA. Collectively, this study provides insight into our understanding of early stages of BHV-1 infection. PMID:27590675

  19. Activities of Various 4-Aminoquinolines Against Infections with Chloroquine-Resistant Strains of Plasmodium falciparum1

    PubMed Central

    Schmidt, L. H.; Vaughan, Dennis; Mueller, Donna; Crosby, Ruth; Hamilton, Rebecca

    1977-01-01

    The studies reported here stemmed from a personal report by Geiman on the capacity of the 4-aminoquinoline amodiaquin to inhibit in vitro maturation of ring stages of the chloroquine-resistant Monterey strain of Plasmodium falciparum. This observation, confirmed in owl monkeys infected with this strain, led to a comparison of the activities of chloroquine, amodiaquin, amopyroquin, and dichlorquinazine (12,278 RP) against infections with various chloroquine-susceptible and chloroquine-resistant strains. The results showed that: (i) these 4-aminoquinolines were essentially equally active against infections with chloroquine-susceptible strains and (ii) the activities of amodiaquin, amopyroquin, and dichlorquinazine were reduced significantly in the face of chloroquine resistance, but (iii) well-tolerated doses of these compounds would cure infections with strains that fully resisted treatment with maximally tolerated doses of chloroquine. Two other 4-aminoquinolines, SN-8137 and SN-9584, which also exhibited activity against chloroquine-resistant parasites in vitro, displayed curative activity in monkeys infected with a chloroquine-resistant strain. These observations show that there is cross-resistance among the 4-aminoquinolines, confirming earlier findings, but indicate that the dimensions of this phenomenon are sufficiently limited so that some derivatives are therapeutically effective against infections refractory to maximally tolerated doses of chloroquine. PMID:406829

  20. Adenosine deaminase activity in serum and lymphocytes of rats infected with Sporothrix schenckii.

    PubMed

    Castro, Verônica S P; Pimentel, Victor C; Da Silva, Aleksandro S; Thomé, Gustavo R; Wolkmer, Patrícia; Castro, Jorge L C; Costa, Márcio M; da Silva, Cássia B; Oliveira, Daniele C; Alves, Sydney H; Schetinger, Maria R C; Lopes, Sonia T A; Mazzanti, Cinthia M

    2012-07-01

    Sporotrichosis is a fungal infection of subcutaneous or chronic evolution, inflammatory lesions characterized by their pyogranulomatous aspect, caused by the dimorphic fungus Sporothrix schenckii. Adenosine deaminase (ADA) is a "key" enzyme in the purine metabolism, promoting the deamination of adenosine, an important anti-inflammatory molecule. The increase in ADA activity has been demonstrated in several inflammatory conditions; however, there are no data in the literature associated with this fungal infection. The objective of this study was to evaluate the activity of serum ADA (S-ADA) and lymphocytes (L-ADA) of rats infected with S. schenckii. We used seventy-eight rats divided into two groups. In the first experiment, rats were infected subcutaneously and in the second experiment, infected intraperitoneally. Blood samples for hematologic evaluation and activities of S-ADA and L-ADA were performed at days 15, 30, and 40 post-infection (PI) to assess disease progression. In the second experiment, it was observed an acute decrease in activity of S-ADA and L-ADA (P < 0.05), suggesting a compensatory mechanism in an attempt to protect the host from excessive tissue damage. With chronicity of disease the rats in the first and second experiment at 30 days PI showed an increased activity of L-ADA (P < 0.05), promoting an inflammatory response in an attempt to combat the spread of the agent. Thus, it is suggested that infection with S. schenckii alters the activities of S-ADA in experimentally infected rats, demonstrating the involvement of this enzyme in the pathogenesis of sporotrichosis.

  1. Cytokine gene polymorphisms and progression-free survival in classical Hodgkin lymphoma by EBV status: Results from two independent cohorts

    PubMed Central

    Ghesquières, Hervé; Maurer, Matthew J.; Casasnovas, Olivier; Ansell, Stephen M.; Larrabee, Beth R.; Lech-Maranda, Eva; Novak, Anne J.; Borrel, Anne-Laure; Slager, Susan L.; Brice, Pauline; Allmer, Cristine; Brion, Annie; Ziesmer, Steven C.; Morschhauser, Franck; Habermann, Thomas M.; Gaillard, Isabelle; Link, Brian K.; Stamatoullas, Aspasia; Fermé, Christophe; Dogan, Ahmet; Macon, William R.; Audouin, Josée; Cerhan, James R.; Salles, Gilles

    2014-01-01

    Background Cytokines are important immune mediators of classical Hodgkin lymphoma (CHL) pathogenesis, and circulating levels at diagnosis may help predict prognosis. Germline single nucleotide polymorphisms (SNPs) in immune genes have been correlated with cytokine production and function. Methods We investigated whether selected germline SNPs in IL10 (rs1800890, rs1800896, rs1800871, rs1800872), TNFA (rs1800629), IL6 (rs1800795), ILRN (rs419598), INFG (rs2430561) and CCL17 (rs223828) were associated with circulating levels of related cytokines at diagnosis and progression-free survival (PFS) in CHL. Patients were from France (GELA, N = 464; median age = 32 years) and the United States (Iowa/Mayo Specialized Program Of Research Excellence [SPORE], N = 239; median age = 38 years); 22% of 346 CHL cases with EBV tumor status were positive. Results There was no association with any of the SNPs with cytokine levels. Overall, there was no association of any of the SNPs with PFS. In exploratory analyses by EBV status, TNFA rs1800629 (HRAA/AG = 2.41; 95%CI, 1.17–4.94) was associated with PFS in EBV-negative GELA patients, with similar trends in the SPORE patients (HRAA/AG = 1.63; 95%CI, 0.61–4.40). In a meta-analysis of the two studies, TNFA (HRAA/AG = 2.11; 95%CI, 1.18–3.77; P = 0.01) was statistically significant, and further adjustment for the international prognostic system did not alter this result. Conclusions This study showed that germline variation in TNFA was associated with CHL prognosis for EBV-negative patients, which will require confirmation. These results support broader studies on the differential impact of genetic variation in immune genes on EBV-positive vs. EBV-negative CHL pathogenesis. PMID:24008079

  2. Expression of bovine vitamin K-dependent carboxylase activity in baculovirus-infected insect cells.

    PubMed

    Roth, D A; Rehemtulla, A; Kaufman, R J; Walsh, C T; Furie, B; Furie, B C

    1993-09-15

    A vitamin K-dependent carboxylase has recently been purified from bovine liver microsomes and candidate cDNA clones have been isolated. Definitive identification of the carboxylase remains circumstantial since expression of candidate carboxylase cDNAs in mammalian cells is confounded by the presence of endogenous carboxylase activity. To overcome this problem, a recombinant strain of baculovirus (Autographa california nuclear polyhedrosis virus, AcMNPV) encoding a putative carboxylase (vbCbx/AcMNPV) was used to infect Sf9 insect cells, which we demonstrate have no endogenous carboxylase activity. Infection with vbCbx/AcMNPV conferred vitamin K-dependent carboxylase activity to Sf9 insect cells. Carboxylase activity was demonstrated to peak 2-3 days after infection with vbCbx/AcMNPV. Metabolic radiolabeling with L-[35S]methionine revealed that the 90-kDa recombinant protein is the major protein synthesized at the time of peak activity after infection. An anti-peptide antibody directed against residues 86-99 reacted with bovine liver carboxylase on Western blot analysis and immunoprecipitated recombinant carboxylase from infected Sf9 microsomal protein preparations. Since Sf9 insect cells lack endogenous vitamin K-dependent carboxylase activity, expression of carboxylase activity in Sf9 insect cells with recombinant baculovirus demonstrates that the protein encoded by this cDNA is a vitamin K-dependent gamma-glutamyl carboxylase. PMID:8378308

  3. Long term results of mechanical prostheses for treatment of active infective endocarditis

    PubMed Central

    Guerra, J; Tornos, M; Permanyer-Miralda, G; Almirante, B; Murtra, M; Soler-Soler, J

    2001-01-01

    OBJECTIVE—To analyse the long term results of mechanical prostheses for treating active infective endocarditis.
DESIGN—Prospective cohort study of a consecutive series of patients diagnosed with infective endocarditis and operated on in the active phase of the infection for insertion of a mechanical prosthesis.
SETTING—Tertiary referral centre in a metropolitan area.
RESULTS—Between 1975 and 1997, 637 cases of infective endocarditis were diagnosed in the centre. Of these, 436 were left sided (with overall mortality of 20.3%). Surgical treatment in the active phase of the infection was needed in 141 patients (72% native, 28% prosthetic infective endocarditis). Mechanical prostheses were used in 131 patients. Operative mortality was 30.5% (40 patients). Ninety one survivors were followed up prospectively for (mean (SD)) 5.4 (4.5) years. Thirteen patients developed prosthetic valve dysfunction. Nine patients suffered reinfection: four of these (4%) were early and five were late. The median time from surgery for late reinfection was 1.4 years. During follow up, 12 patients died. Excluding operative mortality, actuarial survival was 86.6% at five years and 83.7% at 10 years; actuarial survival free from death, reoperation, and reinfection was 73.1% at five years and 59.8% at 10 years.
CONCLUSIONS—In patients surviving acute infective endocarditis and receiving mechanical prostheses, the rate of early reinfection compares well with reported results of homografts. In addition, prosthesis dysfunction rate is low and long term survival is good. These data should prove useful for comparison with long term studies, when available, using other types of valve surgery in active infective endocarditis.


Keywords: infective endocarditis; surgery; mechanical prosthesis PMID:11410564

  4. The Role of Latently Infected B Cells in CNS Autoimmunity

    PubMed Central

    Márquez, Ana Citlali; Horwitz, Marc Steven

    2015-01-01

    The onset of multiple sclerosis (MS) is caused by both genetic and environmental factors. Among the environmental factors, it is believed that previous infection with Epstein–Barr virus (EBV) may contribute in the development of MS. EBV has been associated with other autoimmune diseases, such as systemic lupus erythematous, and cancers like Burkitt’s lymphoma. EBV establishes a life-long latency in B cells with occasional reactivation of the virus throughout the individual’s life. The role played by B cells in MS pathology has been largely studied, yet is not clearly understood. In MS patients, Rituximab, a novel treatment that targets CD20+ B cells, has proven to have successful results in diminishing the number of relapses in remitting relapsing MS; however, the mechanism of how this drug acts has not been clearly established. In this review, we analyze the evidence of how B cells latently infected with EBV might be altering the immune system response and helping in the development of MS. We will also discuss how animal models, such as experimental autoimmune encephalomyelitis (EAE) and murine gammaherpesvirus-68 (γHV-68), can be used as powerful tools in the study of the relationship between EBV, MS, and B cells. PMID:26579121

  5. Macrophage activation and human immunodeficiency virus infection: HIV replication directs macrophages towards a pro-inflammatory phenotype while previous activation modulates macrophage susceptibility to infection and viral production.

    PubMed

    Porcheray, Fabrice; Samah, Boubekeur; Léone, Cathie; Dereuddre-Bosquet, Nathalie; Gras, Gabriel

    2006-05-25

    Macrophages are pivotal for the regulation of immune and inflammatory responses, but whether their role in HIV infection is protective or deleterious remains unclear. In this study, we investigated the effect of pro- and anti-inflammatory stimuli on macrophage sensitivity to two different aspects of HIV infection: their susceptibility to infection stricto sensu, which we measured by endpoint titration method, and their ability to support virus spread, which we measured by using an RT activity assay in infection kinetics. We show a partially protective role for pro-inflammatory agents as well as for IL-4. We also illustrate that various different stimuli display differential effects on macrophage susceptibility to HIV and on virus replication that occurs thereafter. On the other hand, HIV replication strongly repressed CD206 and CD163 expression, thus clearly orientating macrophages towards a pro-inflammatory phenotype, but independently of TNF. Taken together, our results emphasize that HIV infection of macrophages sets up inflammation at the cell level but through unexpected mechanisms. This may limit target susceptibility and participate in virus clearance but may also result in tissue damage.

  6. Treatment of primary HIV-1 infection with cyclosporin A coupled with highly active antiretroviral therapy

    PubMed Central

    Rizzardi, G. Paolo; Harari, Alexandre; Capiluppi, Brunella; Tambussi, Giuseppe; Ellefsen, Kim; Ciuffreda, Donatella; Champagne, Patrick; Bart, Pierre-Alexandre; Chave, Jean-Philippe; Lazzarin, Adriano; Pantaleo, Giuseppe

    2002-01-01

    Primary HIV-1 infection causes extensive immune activation, during which CD4+ T cell activation supports massive HIV-1 production. We tested the safety and the immune-modulating effects of combining cyclosporin A (CsA) treatment with highly active antiretroviral therapy (HAART) during primary HIV-1 infection. Nine adults with primary HIV-1 infection were treated with CsA along with HAART. At week 8, all patients discontinued CsA but maintained HAART. Viral replication was suppressed to a comparable extent in the CsA + HAART cohort and in 29 control patients whose primary infection was treated with HAART alone. CsA restored normal CD4+ T cell levels, both in terms of percentage and absolute numbers. The increase in CD4+ T cells was apparent within a week and persisted throughout the study period. CsA was not detrimental to virus-specific CD8+ or CD4+ T cell responses. At week 48, the proportion of IFN-γ–secreting CD4+ and CD4+CCR7– T cells was significantly higher in the CsA + HAART cohort than in the HAART-alone cohort. In conclusion, rapid shutdown of T cell activation in the early phases of primary HIV-1 infection can have long-term beneficial effects and establish a more favorable immunologic set-point. Appropriate, immune-based therapeutic interventions may represent a valuable complement to HAART for treating HIV infection. PMID:11877476

  7. Activated natural killer cells accelerate liver damage in patients with chronic hepatitis B virus infection.

    PubMed

    Zheng, Q; Zhu, Y Y; Chen, J; Ye, Y B; Li, J Y; Liu, Y R; Hu, M L; Zheng, Y C; Jiang, J J

    2015-06-01

    Emerging evidence indicates that natural killer (NK) cells may contribute to liver injury in patients with hepatitis B virus (HBV) infection. Because HBV infection progresses through various disease phases, the cytolytic profiles of peripheral and intrahepatic NK cells in HBV-infected patients remain to be defined. In this study, we comprehensively characterized intrahepatic and peripheral NK cells in a cohort of HBV-infected individuals, and investigated their impact on liver pathogenesis during chronic HBV infection. The study population included 34 immune-clearance (IC) patients, 36 immune-tolerant (IT) carriers and 10 healthy subjects. We found that the activity of peripheral NK cells from IC patients was functionally elevated compared to IT carriers and controls, and NK cell activation was indicated by an increased expression of CD69, CD107a, interferon (IFN)-γ and tumour necrosis factor (TNF)-α. Further analysis showed that the increased activity of both peripheral and hepatic NK cells was correlated positively with liver injury, which was assessed by serum alanine aminotransferase levels (ALT) and the liver histological activity index (HAI). Interestingly, the frequency of peripheral NK cells was reduced in IC patients (especially those with higher HAI scores of 3-4), but there was a concomitant increase in hepatic NK cells. The functionally activated NK cells are enriched preferentially in the livers of IC patients and skew towards cytolytic activity that accelerates liver injury in chronic hepatitis B (CHB) patients.

  8. Nuclease Activity of Legionella pneumophila Cas2 Promotes Intracellular Infection of Amoebal Host Cells

    PubMed Central

    Gunderson, Felizza F.; Mallama, Celeste A.; Fairbairn, Stephanie G.

    2014-01-01

    Legionella pneumophila, the primary agent of Legionnaires' disease, flourishes in both natural and man-made environments by growing in a wide variety of aquatic amoebae. Recently, we determined that the Cas2 protein of L. pneumophila promotes intracellular infection of Acanthamoeba castellanii and Hartmannella vermiformis, the two amoebae most commonly linked to cases of disease. The Cas2 family of proteins is best known for its role in the bacterial and archeal clustered regularly interspaced short palindromic repeat (CRISPR)–CRISPR-associated protein (Cas) system that constitutes a form of adaptive immunity against phage and plasmid. However, the infection event mediated by L. pneumophila Cas2 appeared to be distinct from this function, because cas2 mutants exhibited infectivity defects in the absence of added phage or plasmid and since mutants lacking the CRISPR array or any one of the other cas genes were not impaired in infection ability. We now report that the Cas2 protein of L. pneumophila has both RNase and DNase activities, with the RNase activity being more pronounced. By characterizing a catalytically deficient version of Cas2, we determined that nuclease activity is critical for promoting infection of amoebae. Also, introduction of Cas2, but not its catalytic mutant form, into a strain of L. pneumophila that naturally lacks a CRISPR-Cas locus caused that strain to be 40- to 80-fold more infective for amoebae, unequivocally demonstrating that Cas2 facilitates the infection process independently of any other component encoded within the CRISPR-Cas locus. Finally, a cas2 mutant was impaired for infection of Willaertia magna but not Naegleria lovaniensis, suggesting that Cas2 promotes infection of most but not all amoebal hosts. PMID:25547789

  9. Chlamydial infection of monocytes stimulates IL-1beta secretion through activation of the NLRP3 inflammasome.

    PubMed

    Abdul-Sater, Ali A; Saïd-Sadier, Najwane; Padilla, Eduardo V; Ojcius, David M

    2010-08-01

    Chlamydia trachomatis infections represent the leading cause of bacterial sexually-transmitted disease in the United States and can cause serious tissue damage leading to infertility and ectopic pregnancies in women. Inflammation and hence the innate immune response to chlamydial infection contributes significantly to tissue damage, particularly by secreting proinflammatory cytokines such as interleukin (IL)-1beta from monocytes, macrophages and dendritic cells. Here we demonstrate that C. trachomatis or Chlamydia muridarum infection of a monocytic cell line leads to caspase-1 activation and IL-1beta secretion through a process requiring the NLRP3 inflammasome. Thus, secretion of IL-1beta decreased significantly when cells were depleted of NLRP3 or treated with the anti-inflammatory inhibitors parthenolide or Bay 11-7082, which inhibit inflammasomes and the transcription factor NF-kappaB. As for other infections causing NRLP3 inflammasome assembly, caspase-1 activation in monocytes is triggered by potassium efflux and reactive oxygen species production. However, anti-oxidants inhibited IL-1beta secretion only partially. Atypically for a bacterial infection, caspase-1 activation during chlamydial infection also involves partially the spleen tyrosine kinase (Syk), which is usually associated with a pathogen recognition receptor for fungal pathogens. Secretion of IL-1beta during infection by many bacteria requires both microbial products from the pathogen and an exogenous danger signal, but chlamydial infection provides both the pathogen-associated molecular patterns and danger signals necessary for IL-1beta synthesis and its secretion from human monocytes. Use of inhibitors that target the inflammasome in animals should therefore dampen inflammation during chlamydial infection.

  10. Epstein-Barr Virus Latent Membrane Protein 2A (LMP2A)-Mediated changes in Fas Expression and Fas-Dependent Apoptosis: Role of Lyn/Syk activation

    PubMed Central

    Incrocci, Ryan; Hussain, Samira; Stone, Amanda; Bieging, Kathryn; Alt, Lauren A.C.; Fay, Michael J.; Swanson-Mungerson, Michelle

    2015-01-01

    Epstein-Barr virus Latent Membrane Protein 2A (LMP2A) is expressed in EBV-infected B cells in the germinal center, a site of significant apoptosis induced by engagement of Fas on activated B cells. Signals from the B cell receptor (BCR) protect germinal center B cells from Fas-mediated apoptosis, and since LMP2A is a BCR mimic, we hypothesized that LMP2A would also protect B cells from Fas-mediated apoptosis. Surprisingly, latently-infected human and murine B cell lines expressing LMP2A were more sensitive to Fas-mediated apoptosis, as determined by increases in Annexin-V staining, and cleavage of caspase-8, −3 and PARP. Additional studies show that LMP2A-expressing B cell lines demonstrate a Lyn- and Syk-dependent increase in sensitivity to Fas-mediated apoptosis, due to an LMP2A-dependent enhancement in Fas expression. These findings demonstrate the ability for LMP2A to directly increase a pro-apoptotic molecule and have implications for EBV latency as well as the treatment of EBV-associated malignancies. PMID:26255694

  11. PPARγ-mediated increase in glucose availability sustains chronic Brucella abortus infection in alternatively activated macrophages

    PubMed Central

    Xavier, Mariana N.; Winter, Maria G.; Spees, Alanna M.; den Hartigh, Andreas B.; Nguyen, Kim; Roux, Christelle M.; Silva, Teane M. A.; Atluri, Vidya L.; Kerrinnes, Tobias; Keestra, A. Marijke; Monack, Denise M.; Luciw, Paul A.; Eigenheer, Richard A.; Bäumler, Andreas J.; Santos, Renato L.; Tsolis, Renée M.

    2013-01-01

    SUMMARY Eradication of persistent intracellular bacterial pathogens with antibiotic therapy is often slow or incomplete. However, strategies to augment antibiotics are hampered by our poor understanding of the nutritional environment that sustains chronic infection. Here we show that the intracellular pathogen Brucella abortus survives and replicates preferentially in alternatively activated macrophages (AAM), which are more abundant during chronic infection. A metabolic shift induced by peroxisome proliferator activated receptor γ (PPARγ), which increases intracellular glucose availability, is identified as a causal mechanism promoting enhanced bacterial survival in AAM. Glucose uptake was crucial for increased replication of B. abortus in AAM, and chronic infection, as inactivation of the bacterial glucose transporter gluP reduced both intracellular survival in AAM and persistence in mice. Thus, a shift in intracellular nutrient availability induced by PPARγ promotes chronic persistence of B. abortus within AAM and targeting this pathway may aid in eradicating chronic infection. PMID:23954155

  12. PPARγ-mediated increase in glucose availability sustains chronic Brucella abortus infection in alternatively activated macrophages.

    PubMed

    Xavier, Mariana N; Winter, Maria G; Spees, Alanna M; den Hartigh, Andreas B; Nguyen, Kim; Roux, Christelle M; Silva, Teane M A; Atluri, Vidya L; Kerrinnes, Tobias; Keestra, A Marijke; Monack, Denise M; Luciw, Paul A; Eigenheer, Richard A; Bäumler, Andreas J; Santos, Renato L; Tsolis, Renée M

    2013-08-14

    Eradication of persistent intracellular bacterial pathogens with antibiotic therapy is often slow or incomplete. However, strategies to augment antibiotics are hampered by our poor understanding of the nutritional environment that sustains chronic infection. Here we show that the intracellular pathogen Brucella abortus survives and replicates preferentially in alternatively activated macrophages (AAMs), which are more abundant during chronic infection. A metabolic shift induced by peroxisome proliferator-activated receptor γ (PPARγ), which increases intracellular glucose availability, is identified as a causal mechanism promoting enhanced bacterial survival in AAMs. Glucose uptake was crucial for increased replication of B. abortus in AAMs, and for chronic infection, as inactivation of the bacterial glucose transporter gluP reduced both intracellular survival in AAMs and persistence in mice. Thus, a shift in intracellular nutrient availability induced by PPARγ promotes chronic persistence of B. abortus within AAMs, and targeting this pathway may aid in eradicating chronic infection. PMID:23954155

  13. PD-1 blockade during chronic SIV infection reduces hyperimmune activation and microbial translocation in rhesus macaques.

    PubMed

    Dyavar Shetty, Ravi; Velu, Vijayakumar; Titanji, Kehmia; Bosinger, Steven E; Freeman, Gordon J; Silvestri, Guido; Amara, Rama Rao

    2012-05-01

    Hyperimmune activation is a strong predictor of disease progression during pathogenic immunodeficiency virus infections and is mediated in part by sustained type I IFN signaling in response to adventitious microbial infection. The immune inhibitory receptor programmed death-1 (PD-1) regulates functional exhaustion of virus-specific CD8(+) T cells during chronic infections, and in vivo PD-1 blockade has been shown to improve viral control of SIV. Here, we show that PD-1 blockade during chronic SIV infection markedly reduced the expression of transcripts associated with type I IFN signaling in the blood and colorectal tissue of rhesus macaques (RMs). The effect of PD-1 blockade on type I IFN signaling was durable and persisted even under conditions of high viremia. Reduced type I IFN signaling was associated with enhanced expression of some of the junction-associated genes in colorectal tissue and with a profound decrease in plasma LPS levels, suggesting a possible repair of gut-associated junctions and decreased microbial translocation into the blood. PD-1 blockade enhanced immunity to gut-resident pathogenic bacteria, control of gut-associated opportunistic infections, and survival of SIV-infected RMs. Our results suggest PD-1 blockade as a potential novel therapeutic approach to enhance combination antiretroviral therapy by suppressing hyperimmune activation in HIV-infected individuals. PMID:22523065

  14. Bacterial Manipulation of NK Cell Regulatory Activity Increases Susceptibility to Listeria monocytogenes Infection

    PubMed Central

    Guthrie, Brandon S.; Schmidt, Rebecca L.; Jamieson, Amanda; Merkel, Patricia; Knight, Vijaya; Cole, Caroline M.; Raulet, David H.; Lenz, Laurel L.

    2016-01-01

    Natural killer (NK) cells produce interferon (IFN)-γ and thus have been suggested to promote type I immunity during bacterial infections. Yet, Listeria monocytogenes (Lm) and some other pathogens encode proteins that cause increased NK cell activation. Here, we show that stimulation of NK cell activation increases susceptibility during Lm infection despite and independent from robust NK cell production of IFNγ. The increased susceptibility correlated with IL-10 production by responding NK cells. NK cells produced IL-10 as their IFNγ production waned and the Lm virulence protein p60 promoted induction of IL-10 production by mouse and human NK cells. NK cells consequently exerted regulatory effects to suppress accumulation and activation of inflammatory myeloid cells. Our results reveal new dimensions of the role played by NK cells during Lm infection and demonstrate the ability of this bacterial pathogen to exploit the induction of regulatory NK cell activity to increase host susceptibility. PMID:27295349

  15. Thrombin activation and liver inflammation in advanced hepatitis C virus infection

    PubMed Central

    González-Reimers, Emilio; Quintero-Platt, Geraldine; Martín-González, Candelaria; Pérez-Hernández, Onán; Romero-Acevedo, Lucía; Santolaria-Fernández, Francisco

    2016-01-01

    Hepatitis C virus (HCV) infection is associated with increased thrombotic risk. Several mechanisms are involved including direct endothelial damage by the HCV virus, with activation of tissue factor, altered fibrinolysis and increased platelet aggregation and activation. In advanced stages, chronic HCV infection may evolve to liver cirrhosis, a condition in which alterations in the portal microcirculation may also ultimately lead to thrombin activation, platelet aggregation, and clot formation. Therefore in advanced HCV liver disease there is an increased prevalence of thrombotic phenomena in portal vein radicles. Increased thrombin formation may activate hepatic stellate cells and promote liver fibrosis. In addition, ischemic changes derived from vascular occlusion by microthrombi favor the so called parenchymal extinction, a process that promotes collapse of hepatocytes and the formation of gross fibrous tracts. These reasons may explain why advanced HCV infection may evolve more rapidly to end-stage liver disease than other forms of cirrhosis. PMID:27182154

  16. A Virtual Look at Epstein–Barr Virus Infection: Biological Interpretations

    PubMed Central

    Delgado-Eckert, Edgar; Hadinoto, Vey; Jarrah, Abdul S; Laubenbacher, Reinhard; Lee, Kichol; Luzuriaga, Katherine; Polys, Nicholas F; Thorley-Lawson, David A

    2007-01-01

    The possibility of using computer simulation and mathematical modeling to gain insight into biological and other complex systems is receiving increased attention. However, it is as yet unclear to what extent these techniques will provide useful biological insights or even what the best approach is. Epstein–Barr virus (EBV) provides a good candidate to address these issues. It persistently infects most humans and is associated with several important diseases. In addition, a detailed biological model has been developed that provides an intricate understanding of EBV infection in the naturally infected human host and accounts for most of the virus' diverse and peculiar properties. We have developed an agent-based computer model/simulation (PathSim, Pathogen Simulation) of this biological model. The simulation is performed on a virtual grid that represents the anatomy of the tonsils of the nasopharyngeal cavity (Waldeyer ring) and the peripheral circulation—the sites of EBV infection and persistence. The simulation is presented via a user friendly visual interface and reproduces quantitative and qualitative aspects of acute and persistent EBV infection. The simulation also had predictive power in validation experiments involving certain aspects of viral infection dynamics. Moreover, it allows us to identify switch points in the infection process that direct the disease course towards the end points of persistence, clearance, or death. Lastly, we were able to identify parameter sets that reproduced aspects of EBV-associated diseases. These investigations indicate that such simulations, combined with laboratory and clinical studies and animal models, will provide a powerful approach to investigating and controlling EBV infection, including the design of targeted anti-viral therapies. PMID:17953479

  17. Nasopharyngeal Infection of Mice with Streptococcus pyogenes and In Vivo Detection of Superantigen Activity.

    PubMed

    Zeppa, Joseph J; Wakabayashi, Adrienne T; Kasper, Katherine J; Xu, Stacey X; Haeryfar, S M Mansour; McCormick, John K

    2016-01-01

    Streptococcus pyogenes is a globally prominent human-specific pathogen that is responsible for an enormous burden of infectious disease. Despite intensive experimental efforts to understand the molecular correlates that contribute to invasive infections, there has been less focus on S. pyogenes carriage and local infection of the nasopharynx. This chapter describes an acute nasopharyngeal infection model in mice that is utilized in our laboratory to study the role of superantigen toxins in the biology of S. pyogenes. We also describe a method to detect superantigen-specific T cell activation in vivo.

  18. Autoimmunity, polyclonal B-cell activation and infection.

    PubMed

    Granholm, N A; Cavallo, T

    1992-02-01

    It is widely believed that autoimmunity is an integral part of the immune system, and that genetic, immunologic, hormonal, environmental and other factors contribute to the pathogenesis of autoimmune disease. Thus, autoimmune disease may represent an abnormal expression of immune functions instead of loss of tolerance to self, and it can be organ specific or systemic in its manifestations. We review the various factors that contribute to the development of autoimmune disease; we also review the mechanisms of polyclonal B-cell activation, with emphasis on the role of infectious agents. We consider systemic lupus erythematosus in humans and in experimental animals as prototypic autoimmune disease, and we summarize data to indicate that polyclonal B-cell activation is central to the pathogenesis of systemic autoimmune disease. The effect of polyclonal B-cell activation, brought about by injections of a B-cell activator-lipopolysaccharide from Gram-negative bacteria-is sufficient to cause autoimmune disease in an immunologically normal host. In fact, autoimmune disease can be arrested if excessive polyclonal B-cell activation is suppressed; alternatively, autoimmune disease can be exacerbated if polyclonal B-cell activation is enhanced. We explore the mechanism of tissue injury when autoimmune disease is induced or exacerbated, and we consider the pathogenic roles of autoantibodies, immune complexes, complement, the blood cell carrier system, and the mononuclear phagocyte system. Although polyclonal B-cell activation may be the mechanism whereby various factors can cause or exacerbate systemic autoimmune disease, polyclonal B-cell activation may cause autoimmune disease on its own.

  19. Activities of adenine nucleotide and nucleoside degradation enzymes in platelets of rats infected by Trypanosoma evansi.

    PubMed

    Oliveira, Camila B; Da Silva, Aleksandro S; Vargas, Lara B; Bitencourt, Paula E R; Souza, Viviane C G; Costa, Marcio M; Leal, Claudio A M; Moretto, Maria B; Leal, Daniela B R; Lopes, Sonia T A; Monteiro, Silvia G

    2011-05-31

    Nucleotide and nucleoside-degrading enzymes, such as nucleoside triphosphate diphosphohydrose (NTPDase), 5'-nucleotidase and adenosine deaminase (ADA) are present in the surface membranes of platelets, involved in clotting disturbances of Trypanosoma evansi-infected animals. Thus, this study was aimed at evaluating the activities of these enzymes in platelets of rats experimentally infected with T. evansi. Animals were divided into four groups, according to the level of parasitemia. Blood samples were collected on days 3 (group A: at the beginning of parasitemia), 5 (group B: high parasitemia) and 15 (group C: chronic infection), post-infection. Group D (control group) was composed of non-infected animals for platelet count, separation and enzymatic assays. Animals from groups A and B showed marked thrombocytopenia, but platelet count was not affected in chronically infected rats. NTPDase, 5'-nucleotidase and ADA activities decreased (p<0.05) in platelets from rats of groups A and B, when compared to the control group. In group C, only NTPDase and 5'-nucleoside activities decreased (p<0.001). The correlations between platelet count and nucleotide/nucleoside hydrolysis were positive and statistically significant (p<0.05) in groups A and B. Platelet aggregation was decreased in all infected groups, in comparison to the control group (p<0.05). It is concluded that the alterations observed in the activities of NTPDase, 5'-nucleotidase and ADA in platelets of T. evansi-infected animals might be related to thrombocytopenia, that by reducing the number of platelets, there was less release of ATP and ADP. Another possibility being suggested is that changes have occurred in the membrane of these cells, decreasing the expression of these enzymes in the cell membrane.

  20. Cure of Trypanosoma musculi infection by heat-labile activity in immune plasma.

    PubMed

    Wechsler, D S; Kongshavn, P A

    1984-06-01

    Passive transfer of plasma from a mouse cured of parasitemia to a Trypanosoma musculi-infected host rapidly eliminates parasitemia; this curative activity, presumably mediated by an immunoglobulin, is sensitive to heat treatment (56 degrees C, 30 min). In addition, pretreatment with immune plasma, even after heat treatment, prevents the development of a patent parasitemia in a naive host (protective activity).

  1. Antileishmanial activity of licochalcone A in mice infected with Leishmania major and in hamsters infected with Leishmania donovani.

    PubMed Central

    Chen, M; Christensen, S B; Theander, T G; Kharazmi, A

    1994-01-01

    This study was designed to examine the antileishmanial activity of the oxygenated chalcone licochalcone A in mice and hamsters infected with Leishmania parasites. Intraperitoneal administration of licochalcone A at doses of 2.5 and 5 mg/kg of body weight per day completely prevented lesion development in BALB/c mice infected with Leishmania major. Treatment of hamsters infected with L. donovani with intraperitoneal administration of licochalcone A at a dose of 20 mg/kg of body weight per day for 6 consecutive days resulted in a > 96% reduction of parasite load in the liver and the spleen compared with values for untreated control animals. The [3H]thymidine uptake by the parasites isolated from the treated hamsters was only about 1% of that observed in parasites isolated from the controls. Oral administration of licochalcone A at concentrations of 5 to 150 mg/kg of body weight per day for 6 consecutive days resulted in > 65 and 85% reductions of L. donovani parasite loads in the liver and the spleen, respectively, compared with those of untreated control hamsters. These data clearly demonstrate that licochalcone A is a promising lead for the development of a new drug against leishmaniases. PMID:8092835

  2. Effects of rutin and quercetin on monooxygenase activities in experimental influenza virus infection.

    PubMed

    Savov, Varban M; Galabov, Angel S; Tantcheva, Lyubka P; Mileva, Milka M; Pavlova, Elitsa L; Stoeva, Emilia S; Braykova, Ana A

    2006-08-01

    The aim of this work is to study the effect of the flavonoids rutin and quercetin on hepatic monooxygenase activities in experimental influenza virus infection (EIVI). EIVI causes oxidative stress in the whole organism. This is confirmed by the rapidly increased concentrations of thiobarbituric reactive substances in influenza-infected mice: lungs - 290%; blood plasma - more than 320%; liver - 230%; brain - 50%. Although known for their antioxidant activities, rutin and quercetin exhibit prooxidant effect in healthy and antioxidant activity in influenza-infected animals. The pretreatment with both flavonoids (20 mg/kg b.w.) restores oxidative damage mostly in the target organ of the infection as well as in the liver of all infected mice (lungs: rutin - 30%, quercetin - 40%, combination - 45%; liver: rutin - 12%; quercetin - 40%; combination - 50%). As far as EIVI causes oxidative stress, toxicosis and inhibition of the hepatic monooxygenase activity, it is important to study the effects of rutin and quercetin on these systems. Both flavonoids induce the level of cytochrome P-450 (rutin - 13%, quercetin - 30%, combination - 22%) but inactivate NADPH-cytochrome c reductase, aminopyrine N-demethylase and analgin N-demethylase on the 5th day of EIVI. Probably, these flavonoids affect different components of the monooxygenase system. These effects could be explained with oxidative hepatic intoxication on the 5th critical day of EIVI as well as higher dose treatment. More data are needed on the antioxidant/prooxidant effects of rutin and quercetin, probably due to specific metabolic and physiological activities, chemical structure, etc.

  3. IL-15 promotes activation and expansion of CD8+ T cells in HIV-1 infection

    PubMed Central

    Younes, Souheil-Antoine; Freeman, Michael L.; Mudd, Joseph C.; Shive, Carey L.; Reynaldi, Arnold; Estes, Jacob D.; Deleage, Claire; Lucero, Carissa; Anderson, Jodi; Schacker, Timothy W.; Davenport, Miles P.; McCune, Joseph M.; Hunt, Peter W.; Lee, Sulggi A.; Debernardo, Robert L.; Jacobson, Jeffrey M.; Canaday, David H.; Sekaly, Rafick-Pierre; Sieg, Scott F.; Lederman, Michael M.

    2016-01-01

    In HIV-1–infected patients, increased numbers of circulating CD8+ T cells are linked to increased risk of morbidity and mortality. Here, we identified a bystander mechanism that promotes CD8 T cell activation and expansion in untreated HIV-1–infected patients. Compared with healthy controls, untreated HIV-1–infected patients have an increased population of proliferating, granzyme B+, CD8+ T cells in circulation. Vβ expression and deep sequencing of CDR3 revealed that in untreated HIV-1 infection, cycling memory CD8 T cells possess a broad T cell repertoire that reflects the repertoire of the resting population. This suggests that cycling is driven by bystander activation, rather than specific antigen exposure. Treatment of peripheral blood mononuclear cells with IL-15 induced a cycling, granzyme B+ phenotype in CD8+ T cells. Moreover, elevated IL-15 expression in the lymph nodes of untreated HIV-1–infected patients correlated with circulating CD8+ T cell counts and was normalized in these patients following antiretroviral therapy. Together, these results suggest that IL-15 drives bystander activation of CD8+ T cells, which predicts disease progression in untreated HIV-1–infected patients and suggests that elevated IL-15 may also drive CD8+ T cell expansion that is linked to increased morbidity and mortality in treated patients. PMID:27322062

  4. Localization and activity of various lysosomal proteases in Leishmania amazonensis-infected macrophages.

    PubMed Central

    Prina, E; Antoine, J C; Wiederanders, B; Kirschke, H

    1990-01-01

    In mammalian hosts, Leishmania amastigotes are obligatory intracellular parasites of macrophages and multiply within parasitophorous vacuoles of phagolysosomal origin. To understand how they escape the harmful strategies developed by macrophages to kill ingested microorganisms, it is important to obtain information on the functional state of parasitophorous vacuole. For this purpose, we studied the intracellular distribution and activity of host lysosomal proteases in rat bone marrow-derived macrophages infected with Leishmania amazonensis amastigotes. Localization of cathepsins B, H, L, and D was investigated by using specific immunoglobulins. In uninfected macrophages, these enzymes were located in perinuclear granules (most of them were probably secondary lysosomes) which, after infection, disappeared progressively. In infected macrophages, cathepsins were detected mainly in the parasitophorous vacuoles, suggesting that the missing secondary lysosomes had fused with these organelles. Biochemical assays of various proteases (cathepsins B, H, and D and dipeptidyl peptidases I and II) showed that infection was accompanied by a progressive increase of all activities tested, except that of dipeptidyl peptidase II, which remained constant. No more than 1 to 10% of these activities could be attributed to amastigotes. These data indicate that (i) Leishmania infection is followed by an increased synthesis and/or a reduced catabolism of host lysosomal proteases, and (ii) amastigotes grow in a compartment rich in apparently fully active proteases. Unexpectedly, it was found that infected and uninfected macrophages degraded endocytosed proteins similarly. The lack of correlation in infected macrophages between increase of protease activities and catabolism of exogenous proteins could be linked to the huge increase in volume of the lysosomal compartment. Images PMID:2187806

  5. RAAS Activation Is Associated With Visceral Adiposity and Insulin Resistance Among HIV-infected Patients

    PubMed Central

    Srinivasa, Suman; Fitch, Kathleen V.; Wong, Kimberly; Torriani, Martin; Mayhew, Caitlin; Stanley, Takara; Lo, Janet; Adler, Gail K.

    2015-01-01

    Context: Little is known about renin-angiotensin-aldosterone system (RAAS) activation in relationship to visceral adipose tissue (VAT) accumulation in HIV-infected patients, a population at significant risk for insulin resistance and other metabolic disease. Design: Twenty HIV and 10 non-HIV-infected subjects consumed a standardized low sodium or liberal sodium diet to stimulate or suppress the RAAS, respectively. RAAS parameters were evaluated in response to each diet and a graded angiotensin II infusion. Further analyses were performed after groups were substratified by median VAT measured by magnetic resonance imaging. Results: Aldosterone concentrations during the low-sodium diet were higher in HIV than non-HIV-infected subjects [13.8 (9.7, 30.9) vs 9.2 (7.6, 13.6) ng/dL, P = .03] and increased across groups stratified by visceral adipose tissue (VAT) [8.5 (7.1, 12.8), 9.2 (8.1, 21.5), 11.4 (9.4, 13.8), and 27.2 (13.0, 36.9) ng/dL in non-HIV-infected without increased VAT, non-HIV-infected with increased VAT, HIV-infected without increased VAT, HIV-infected with increased VAT, respectively, overall trend P = .02]. Under this condition, plasma renin activity [3.50 (2.58, 4.65) vs 1.45 (0.58, 2.33) ng/mL · h, P = .002] was higher among the HIV-infected subjects with vs without increased VAT. Differences in the suppressibility of plasma renin activity by graded angiotensin infusion were seen stratifying by VAT among the HIV-infected group (P < .02 at each dose). In addition, aldosterone (P = .007) was an independent predictor of insulin resistance in multivariate modeling, controlling for VAT and adiponectin. Conclusion: These data suggest excess RAAS activation in relationship to visceral adiposity in HIV-infected patients that may independently contribute to insulin resistance. Mineralocorticoid blockade may have therapeutic potential to reduce metabolic complications in HIV-infected patients with increased visceral adiposity. PMID:26086328

  6. Molecular Mechanisms of Inflammasome Activation during Microbial Infections

    PubMed Central

    Broz, Petr; Monack, Denise M.

    2011-01-01

    Summary The innate immune system plays a crucial role in the rapid recognition and elimination of invading microbes. Detection of microbes relies on germ-line encoded pattern recognition receptors (PRRs) that recognize essential bacterial molecules, so-called pathogen-associated molecular patterns (PAMPs). A subset of PRRs, belonging to the NOD-like receptor (NLR) and the PYHIN protein families, detects viral and bacterial pathogens in the cytosol of host cells and induces the assembly of a multi-protein signaling platform called the inflammasome. The inflammasome serves as an activation platform for the mammalian cysteine protease caspase-1, a central mediator of innate immunity. Active caspase-1 promotes the maturation and release of interleukin-1β (IL-1β) and IL-18 as well as protein involved in cytoprotection and tissue repair. In addition, caspase-1 initiates a novel form of cell death called pyroptosis. Here we discuss latest advances and our insights on inflammasome stimulation by two model intracellular pathogens, Francisella tularensis and Salmonella typhimurium. Recent studies on these pathogens have significantly shaped our understanding of the molecular mechanisms of inflammasome activation and how microbes can evade or manipulate inflammasome activity. In addition, we review the role of the inflammasome adapter ASC in the caspase-1 autoproteolysis and new insights into the structure of the inflammasome complex. PMID:21884176

  7. Pythium infection activates conserved plant defense responses in mosses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The moss Physcomitrella patens (P. patens) is a useful model to study abiotic stress responses since it is highly tolerant to drought, salt and osmotic stress. However, little is known about the defense mechanisms activated in this moss after pathogen assault. Here the induction of defense responses...

  8. Suppression of the LMP2A target gene, EGR-1, protects Hodgkin's lymphoma cells from entry to the EBV lytic cycle.

    PubMed

    Vockerodt, Martina; Wei, Wenbin; Nagy, Eszter; Prouzova, Zuzana; Schrader, Alexandra; Kube, Dieter; Rowe, Martin; Woodman, Ciaran B; Murray, Paul G

    2013-08-01

    Hodgkin's lymphoma is unusual among B cell lymphomas, in so far as the malignant Hodgkin/Reed-Sternberg (HRS) cells lack a functional B cell receptor (BCR), as well as many of the required downstream signalling components. In Epstein-Barr virus (EBV)-positive cases of Hodgkin's lymphoma, HRS cells express the viral latent membrane proteins (LMP)-1 and -2A. LMP2A is thought to contribute to the pathogenesis of Hodgkin's lymphoma by providing a surrogate BCR-like survival signal. However, LMP2A has also been shown to induce the virus-replicative cycle in B cells, an event presumably incompatible with lymphomagenesis. In an attempt to resolve this apparent paradox, we compared the transcriptional changes observed in primary HRS cells with those induced by LMP2A and by BCR activation in primary human germinal centre (GC) B cells, the presumed progenitors of HRS cells. We found a subset of genes that were up-regulated by both LMP2A expression and BCR activation but which were down-regulated in primary HRS cells. These genes included EGR1, an immediate-early gene that is required for BCR-induced entry to the virus-replicative cycle. We present data supporting a model for the pathogenesis of EBV-positive Hodgkin's lymphoma in which LMP2A-expressing HRS cells lacking BCR signalling functions cannot induce EGR1 and are consequently protected from entry to the virus lytic cycle. The primary microarray data are available from GEO (http://www.ncbi.nlm.nih.gov/geo/) under series Accession No 46143.

  9. Exosomes Derived from HIV-1-infected Cells Contain Trans-activation Response Element RNA*

    PubMed Central

    Narayanan, Aarthi; Iordanskiy, Sergey; Das, Ravi; Van Duyne, Rachel; Santos, Steven; Jaworski, Elizabeth; Guendel, Irene; Sampey, Gavin; Dalby, Elizabeth; Iglesias-Ussel, Maria; Popratiloff, Anastas; Hakami, Ramin; Kehn-Hall, Kylene; Young, Mary; Subra, Caroline; Gilbert, Caroline; Bailey, Charles; Romerio, Fabio; Kashanchi, Fatah

    2013-01-01

    Exosomes are nano-sized vesicles produced by healthy and virus-infected cells. Exosomes derived from infected cells have been shown to contain viral microRNAs (miRNAs). HIV-1 encodes its own miRNAs that regulate viral and host gene expression. The most abundant HIV-1-derived miRNA, first reported by us and later by others using deep sequencing, is the trans-activation response element (TAR) miRNA. In this study, we demonstrate the presence of TAR RNA in exosomes from cell culture supernatants of HIV-1-infected cells and patient sera. TAR miRNA was not in Ago2 complexes outside the exosomes but enclosed within the exosomes. We detected the host miRNA machinery proteins Dicer and Drosha in exosomes from infected cells. We report that transport of TAR RNA from the nucleus into exosomes is a CRM1 (chromosome region maintenance 1)-dependent active process. Prior exposure of naive cells to exosomes from infected cells increased susceptibility of the recipient cells to HIV-1 infection. Exosomal TAR RNA down-regulated apoptosis by lowering Bim and Cdk9 proteins in recipient cells. We found 104–106 copies/ml TAR RNA in exosomes derived from infected culture supernatants and 103 copies/ml TAR RNA in the serum exosomes of highly active antiretroviral therapy-treated patients or long term nonprogressors. Taken together, our experiments demonstrated that HIV-1-infected cells produced exosomes that are uniquely characterized by their proteomic and RNA profiles that may contribute to disease pathology in AIDS. PMID:23661700

  10. Activation and Recruitment of Regulatory T Cells via Chemokine Receptor Activation in Trichinella spiralis-Infected Mice

    PubMed Central

    Ahn, Jeong-Bin; Kang, Shin Ae; Kim, Dong-Hee; Yu, Hak Sun

    2016-01-01

    As most infections by the helminth parasite elicit the recruitment of CD4+CD25+Foxp3+ T (Treg) cells, many scientists have suggested that these cells could be used for the treatment of immune-mediated inflammation and associated diseases. In order to investigate the distribution and alteration of activated Treg cells, we compared the expression levels of Treg cell activation markers in the ileum and gastrocnemius tissues 1, 2, and 4 weeks after infection. The number of Treg cells was monitored using GFP-coded Foxp3 transgenic mice. In mice at 1 week after Trichinella spiralis infection, the number of activated Treg cells was higher than in the control group. In mice at 2 weeks after infection, there was a significant increase in the number of cells expressing Foxp3 and CTLA-4 when compared to the control group and mice at 1 week after infection. At 4 weeks after infection, T. spiralis was easily identifiable in nurse cells in mouse muscles. In the intestine, the expression of Gzmb and Klrg1 decreased over time and that of Capg remained unchanged for the first and second week, then decreased in the 4th week. However, in the muscles, the expression of most chemokine genes was increased due to T. spiralis infection, in particular the expression levels of Gzmb, OX40, and CTLA-4 increased until week 4. In addition, increased gene expression of all chemokine receptors in muscle, CXCR3, CCR4, CCR5, CCR9, and CCR10, was observed up until the 4th week. In conclusion, various chemokine receptors showed increased expressions combined with recruitment of Treg cells in the muscle tissue. PMID:27180574

  11. Activation and Recruitment of Regulatory T Cells via Chemokine Receptor Activation in Trichinella spiralis-Infected Mice.

    PubMed

    Ahn, Jeong-Bin; Kang, Shin Ae; Kim, Dong-Hee; Yu, Hak Sun

    2016-04-01

    As most infections by the helminth parasite elicit the recruitment of CD4(+)CD25(+)Foxp3(+) T (Treg) cells, many scientists have suggested that these cells could be used for the treatment of immune-mediated inflammation and associated diseases. In order to investigate the distribution and alteration of activated Treg cells, we compared the expression levels of Treg cell activation markers in the ileum and gastrocnemius tissues 1, 2, and 4 weeks after infection. The number of Treg cells was monitored using GFP-coded Foxp3 transgenic mice. In mice at 1 week after Trichinella spiralis infection, the number of activated Treg cells was higher than in the control group. In mice at 2 weeks after infection, there was a significant increase in the number of cells expressing Foxp3 and CTLA-4 when compared to the control group and mice at 1 week after infection. At 4 weeks after infection, T. spiralis was easily identifiable in nurse cells in mouse muscles. In the intestine, the expression of Gzmb and Klrg1 decreased over time and that of Capg remained unchanged for the first and second week, then decreased in the 4th week. However, in the muscles, the expression of most chemokine genes was increased due to T. spiralis infection, in particular the expression levels of Gzmb, OX40, and CTLA-4 increased until week 4. In addition, increased gene expression of all chemokine receptors in muscle, CXCR3, CCR4, CCR5, CCR9, and CCR10, was observed up until the 4th week. In conclusion, various chemokine receptors showed increased expressions combined with recruitment of Treg cells in the muscle tissue. PMID:27180574

  12. The Role of Platelet-Activating Factor in Chronic Inflammation, Immune Activation, and Comorbidities Associated with HIV Infection

    PubMed Central

    Kelesidis, Theodoros; Papakonstantinou, Vasiliki; Detopoulou, Paraskevi; Fragopoulou, Elizabeth; Chini, Maria; Lazanas, Marios C.; Antonopoulou, Smaragdi

    2016-01-01

    With the advent of highly effective antiretroviral therapy, cardiovascular disease has become an important cause of morbidity and mortality among people with treated HIV-1, but the pathogenesis is unclear. Platelet-activating factor is a potent lipid mediator of inflammation that has immunomodulatory effects and a pivotal role in the pathogenesis of inflammatory disorders and cardiovascular disease. Limited scientific evidence suggests that the platelet-activating factor pathway may be a mechanistic link between HIV-1 infection, systemic inflammation, and immune activation that contribute to pathogenesis of chronic HIV-related comorbidities, including cardiovascular disease and HIV-associated neurocognitive disorders. In this review, we examine the mechanisms by which the cross-talk between HIV-1, immune dysregulation, inflammation, and perturbations in the platelet-activating factor pathway may directly affect HIV-1 immunopathogenesis. Understanding the role of platelet-activating factor in HIV-1 infection may pave the way for further studies to explore therapeutic interventions, such as diet, that can modify platelet-activating factor activity and use of platelet-activating factor inhibitors that might improve the prognosis of HIV-1 infected patients. PMID:26616844

  13. Active hepatitis C infection and HCV genotypes prevalent among the IDUs of Khyber Pakhtunkhwa.

    PubMed

    ur Rehman, Latif; Ullah, Ihasn; Ali, Ijaz; Khan, Imtiaz Ali; Iqbal, Aqib; Khan, Sanaullah; Khan, Sher Hayat; Zaman, Khaleeq Uz; ullah Khan, Najib; Swati, Zahoor Ahmed; Jahangiri, Anila Tariq

    2011-01-01

    Injection drug users (IDUs) are considered as a high risk group to develop hepatitis C due to needle sharing. In this study we have examined 200 injection drug users from various regions of the Khyber Pakhtunkhwa province for the prevalence of active HCV infection and HCV genotypes by Immunochromatographic assays, RT-PCR and Type-specific PCR. Our results indicated that 24% of the IDUs were actively infected with HCV while anti HCV was detected among 31.5% cases. Prevalent HCV genotypes were HCV 2a, 3a, 4 and 1a. Majority of the IDUs were married and had attained primary or middle school education. 95% of the IDUs had a previous history of needle sharing. Our study indicates that the rate of active HCV infection among the IDUs is higher with comparatively more prevalence of the rarely found HCV types in KPK. The predominant mode of HCV transmission turned out to be needle sharing among the IDUs. PMID:21711541

  14. Activated ClpP kills persisters and eradicates a chronic biofilm infection.

    PubMed

    Conlon, B P; Nakayasu, E S; Fleck, L E; LaFleur, M D; Isabella, V M; Coleman, K; Leonard, S N; Smith, R D; Adkins, J N; Lewis, K

    2013-11-21

    Chronic infections are difficult to treat with antibiotics but are caused primarily by drug-sensitive pathogens. Dormant persister cells that are tolerant to killing by antibiotics are responsible for this apparent paradox. Persisters are phenotypic variants of normal cells and pathways leading to dormancy are redundant, making it challenging to develop anti-persister compounds. Biofilms shield persisters from the immune system, suggesting that an antibiotic for treating a chronic infection should be able to eradicate the infection on its own. We reasoned that a compound capable of corrupting a target in dormant cells will kill persisters. The acyldepsipeptide antibiotic (ADEP4) has been shown to activate the ClpP protease, resulting in death of growing cells. Here we show that ADEP4-activated ClpP becomes a fairly nonspecific protease and kills persisters by degrading over 400 proteins, forcing cells to self-digest. Null mutants of clpP arise with high probability, but combining ADEP4 with rifampicin produced complete eradication of Staphylococcus aureus biofilms in vitro and in a mouse model of a chronic infection. Our findings indicate a general principle for killing dormant cells-activation and corruption of a target, rather than conventional inhibition. Eradication of a biofilm in an animal model by activating a protease suggests a realistic path towards developing therapies to treat chronic infections.

  15. Cell death, BAX activation, and HMGB1 release during infection with Chlamydia.

    PubMed

    Jungas, Thomas; Verbeke, Philippe; Darville, Toni; Ojcius, David M

    2004-11-01

    Infection by a number of Chlamydia species leads to resistance of the host cell to apoptosis, followed by induction of host-cell death. In a population of infected cells that displays protection against staurosporine-induced apoptosis among the adherent cells, we find that cells that had been recovered from the supernatant share characteristics of both apoptosis and necrosis, as assayed by the propidium iodide (PI)-annexin V double-labeling technique. Cell death was observed in both an epithelial cell line and primary fibroblasts, although the primary cells had a higher propensity to die through apoptosis than the immortalized cell line. Staurosporine-mediated activation of the pro-apoptotic BCL-2 family member, BAX, was inhibited in the epithelial cell line infected for 32 h with the lymphogranuloma venereum (LGV/L2) but not the murine pneumonitis (MoPn) strain of C. trachomatis, but inhibition of staurosporine-mediated BAX activation disappeared after 48 h of infection with the LGV/L2 strain. Conversely, infection with MoPn (C. muridarum) but not LGV/L2 led to BAX activation after 72 h, as previously reported for shorter (48 h) infection with the guinea pig inclusion conjunctivitis (GPIC) serovar of C. psittaci (C. caviae). These results suggest that the ability to inhibit staurosporine-mediated BAX activation or to activate BAX due to the infection itself may vary as a function of the chlamydial strain. Interestingly, both the epithelial cells and the fibroblasts also released high mobility group box 1 protein (HMGB1) during infection, although much less HMGB1 was released from fibroblasts, consistent with the higher level of apoptosis observed in the primary cells. HMGB1 is released preferentially by necrotic or permeabilized viable cells, but not apoptotic cells. In the extracellular space, HMGB1 promotes inflammation through interaction with specific cell-surface receptors. Higher levels of HMGB1 were also measured in the genital-tract secretions of mice

  16. Cytokine profile and natural killer cell activity in Listeria monocytogenes infected mice treated orally with Petiveria alliacea extract.

    PubMed

    Queiroz, M L; Quadros, M R; Santos, L M

    2000-08-01

    In this work, we investigated the effects of Petiveria alliacea extract on the production of Th1-type and Th2-type cytokines and on NK cells activity in normal and Listeria monocytogenes infected mice. Our results demonstrated that in normal/non-infected mice P. alliacea administration led to increased levels of Interleukin-2 (IL-2). The infection alone enhanced INF-gamma levels and NK cell activity at 48 and 72 hours of infection. The treatment with five consecutive doses of 1000 mg/kg/day of P. alliacea extract, given previously to infection, led to further increases in IL-2 levels, in relation to normal/non-infected/P. alliacea treated controls, and in INF-gamma levels at 72 h of infection, compared to infected mice. On the other hand, the production of IL-4 and IL-10 were not altered either by the infection or by the treatment with P. alliacea extract. NK cells activity increased at 48 h and 72 h following the inoculation of the bacteria. When mice were treated with P. alliacea previously to infection, NK activity was higher than that observed at 48 h, 72 h and 120 h of infection in the infected animal. Based on these findings we suggest that P. alliacea up-regulates anti-bacterial immune response by enhancing both Th1 function and the activity of NK cells.

  17. Small-molecule inhibitors of lethal factor protease activity protect against anthrax infection.

    PubMed

    Moayeri, Mahtab; Crown, Devorah; Jiao, Guan-Sheng; Kim, Seongjin; Johnson, Alan; Leysath, Clinton; Leppla, Stephen H

    2013-09-01

    Bacillus anthracis, the causative agent of anthrax, manifests its pathogenesis through the action of two secreted toxins. The bipartite lethal and edema toxins, a combination of lethal factor or edema factor with the protein protective antigen, are important virulence factors for this bacterium. We previously developed small-molecule inhibitors of lethal factor proteolytic activity (LFIs) and demonstrated their in vivo efficacy in a rat lethal toxin challenge model. In this work, we show that these LFIs protect against lethality caused by anthrax infection in mice when combined with subprotective doses of either antibiotics or neutralizing monoclonal antibodies that target edema factor. Significantly, these inhibitors provided protection against lethal infection when administered as a monotherapy. As little as two doses (10 mg/kg) administered at 2 h and 8 h after spore infection was sufficient to provide a significant survival benefit in infected mice. Administration of LFIs early in the infection was found to inhibit dissemination of vegetative bacteria to the organs in the first 32 h following infection. In addition, neutralizing antibodies against edema factor also inhibited bacterial dissemination with similar efficacy. Together, our findings confirm the important roles that both anthrax toxins play in establishing anthrax infection and demonstrate the potential for small-molecule therapeutics targeting these proteins.

  18. Highly active antiretroviral therapy potently suppresses HIV infection in humanized Rag2-/-gammac-/- mice.

    PubMed

    Sango, Kaori; Joseph, Aviva; Patel, Mahesh; Osiecki, Kristin; Dutta, Monica; Goldstein, Harris

    2010-07-01

    Humanized Rag2(-/-)gamma(c)(-/-) mice (Hu-DKO mice) become populated with functional human T cells, B cells, and dendritic cells following transplantation with human hematopoietic stem cells (HSC) and represent an improved model for studying HIV infection in vivo. In the current study we demonstrated that intrasplenic inoculation of hu-DKO mice with HIV-1 initiated a higher level of HIV infection than intravenous or intraperitoneal inoculation, associated with a reciprocal decrease in peripheral CD4(+) T cells and increase in peripheral CD8(+) T cells. HIV infection by intrasplenic injection increased serum levels of human IgG and IgM including human IgM and IgG specific for HIV-1 gp120. There was a significant inverse correlation between the level of HIV-1 infection and the extent of CD4(+) T cell depletion. Highly active antiretroviral therapy (HAART) initiated 1 week after HIV-1 inoculation markedly suppressed HIV-1 infection and prevented CD4(+) T cell depletion. Taken together, these findings demonstrate that intrasplenic injection of hu-DKO mice with HIV is a more efficient route of HIV infection than intravenous or intraperitoneal injection and generates increased infection associated with an increased anti-HIV humoral response. This animal model can serve as a valuable in vivo model to study the efficacy of anti-HIV therapies.

  19. PKR Activation Favors Infectious Pancreatic Necrosis Virus Replication in Infected Cells

    PubMed Central

    Gamil, Amr A.A.; Xu, Cheng; Mutoloki, Stephen; Evensen, Øystein

    2016-01-01

    The double-stranded RNA-activated protein kinase R (PKR) is a Type I interferon (IFN) stimulated gene that has important biological and immunological functions. In viral infections, in general, PKR inhibits or promotes viral replication, but PKR-IPNV interaction has not been previously studied. We investigated the involvement of PKR during infectious pancreatic necrosis virus (IPNV) infection using a custom-made rabbit antiserum and the PKR inhibitor C16. Reactivity of the antiserum to PKR in CHSE-214 cells was confirmed after IFNα treatment giving an increased protein level. IPNV infection alone did not give increased PKR levels by Western blot, while pre-treatment with PKR inhibitor before IPNV infection gave decreased eukaryotic initiation factor 2-alpha (eIF2α) phosphorylation. This suggests that PKR, despite not being upregulated, is involved in eIF2α phosphorylation during IPNV infection. PKR inhibitor pre-treatment resulted in decreased virus titers, extra- and intracellularly, concomitant with reduction of cells with compromised membranes in IPNV-permissive cell lines. These findings suggest that IPNV uses PKR activation to promote virus replication in infected cells. PMID:27338445

  20. Prevalence of cervical Chlamydia trachomatis infection in sexually active adolescents from Salvador, Brazil.

    PubMed

    Machado, Márcia Sacramento Cunha; Costa e Silva, Bruno Fernando Borges da; Gomes, Igor Logetto Caetité; Santana, Iuri Usêda; Grassi, Maria Fernanda Rios

    2012-01-01

    The incidence of sexually transmitted diseases among adolescents is increasing worldwide. Genital Chlamydia trachomatis infection is one of the most prevalent sexually transmitted diseases in young women, and undetected disease is highly associated with long-term complications in women. Our goal was to determine the prevalence of cervical Chlamydia trachomatis infection in a sexually active population of female adolescents from Salvador, Brazil, and to describe their socio-demographic, behavioral, and clinical characteristics. 100 sexually active adolescents (10-19 years) were included in this study, between 2008 and 2010. Endocervical samples were obtained during gynecological examination. Inhouse polymerase chain reaction of cervical specimens was used for Chlamydia trachomatis detection. The overall prevalence of cervical Chlamydia trachomatis infection was 31% (95% CI 22-40). There were no statistically significant differences in the age at first sexual intercourse, number of sexual partners, and frequency of condom use between Chlamydia infected and uninfected adolescents. The prevalence of cervical Chlamydia trachomatis infection among adolescents from Salvador was the highest in Brazil up to the present date. These results demonstrate an urgent need for continued and comprehensive prevention strategies along with proper screening for Chlamydia in high-risk populations in order to decrease the rates of infection.

  1. PKR Activation Favors Infectious Pancreatic Necrosis Virus Replication in Infected Cells.

    PubMed

    Gamil, Amr A A; Xu, Cheng; Mutoloki, Stephen; Evensen, Øystein

    2016-01-01

    The double-stranded RNA-activated protein kinase R (PKR) is a Type I interferon (IFN) stimulated gene that has important biological and immunological functions. In viral infections, in general, PKR inhibits or promotes viral replication, but PKR-IPNV interaction has not been previously studied. We investigated the involvement of PKR during infectious pancreatic necrosis virus (IPNV) infection using a custom-made rabbit antiserum and the PKR inhibitor C16. Reactivity of the antiserum to PKR in CHSE-214 cells was confirmed after IFNα treatment giving an increased protein level. IPNV infection alone did not give increased PKR levels by Western blot, while pre-treatment with PKR inhibitor before IPNV infection gave decreased eukaryotic initiation factor 2-alpha (eIF2α) phosphorylation. This suggests that PKR, despite not being upregulated, is involved in eIF2α phosphorylation during IPNV infection. PKR inhibitor pre-treatment resulted in decreased virus titers, extra- and intracellularly, concomitant with reduction of cells with compromised membranes in IPNV-permissive cell lines. These findings suggest that IPNV uses PKR activation to promote virus replication in infected cells. PMID:27338445

  2. Descending Mediastinitis in Epstein-Barr Virus Infection

    PubMed Central

    van Driel, E. M.; Janssen, M. J. F. M.

    2015-01-01

    Our case report describes a previously healthy 34-year-old male who develops a descending mediastinitis as a complication of an Epstein-Barr virus (EBV) infection. The mediastinitis was suspected to have developed by a breakthrough of a peritonsillar abscess through the space between the alar and prevertebral space. PMID:25740774

  3. Bacterial Infection of Fly Ovaries Reduces Egg Production and Induces Local Hemocyte Activation

    PubMed Central

    Brandt, Stephanie M.; Schneider, David S.

    2009-01-01

    Summary Morbidity, the state of being diseased, is an important aspect of pathogenesis that has gone relatively unstudied in fruit flies. Our interest is in characterizing how bacterial pathogenesis affects various physiologies of the fly. We chose to examine the fly ovary because we found bacterial infection had a striking effect on fly reproduction. We observed decreased egg laying after bacterial infection that correlated with increased bacterial virulence. We also found that bacteria colonized the ovary in a previously undescribed manner; bacteria were found in the posterior of the ovary, adjacent to the lateral oviduct. This local infection in the ovary resulted in melanization and activation of the cellular immune response at the site of infection. PMID:17400292

  4. Low cost antiviral activity of Plodia interpunctella haemolymph in vivo demonstrated by dose dependent infection.

    PubMed

    Saejeng, A; Siva-Jothy, M T; Boots, M

    2011-02-01

    Given the ubiquity of infectious disease it is important to understand the way in which hosts defend themselves and any costs that they may pay for this defence. Despite this, we know relatively little about insect immune responses to viruses when compared to their well-characterized responses to other pathogens. In particular it is unclear whether there is significant haemocoelic response to viral infection. Here we directly examine this question by examining whether there is a dose-dependency in infection risk when a DNA virus is injected directly into the haemocoel. Infection from direct injection into the haemocoel showed a clear dose dependency that is indicative of an active intrahaemocoelic immune response to DNA viruses in insects. In contrast to the natural oral infection route, we found no measurable sublethal effects in the survivors from direct injection. This suggests that the immune responses in the haemocoel are less costly than those that occur earlier.

  5. Mechanistic insights on immunosenescence and chronic immune activation in HIV-tuberculosis co-infection

    PubMed Central

    Shankar, Esaki M; Velu, Vijayakumar; Kamarulzaman, Adeeba; Larsson, Marie

    2015-01-01

    Immunosenescence is marked by accelerated degradation of host immune responses leading to the onset of opportunistic infections, where senescent T cells show remarkably higher ontogenic defects as compared to healthy T cells. The mechanistic association between T-cell immunosenescence and human immunodeficiency virus (HIV) disease progression, and functional T-cell responses in HIV-tuberculosis (HIV-TB) co-infection remains to be elaborately discussed. Here, we discussed the association of immunosenescence and chronic immune activation in HIV-TB co-infection and reviewed the role played by mediators of immune deterioration in HIV-TB co-infection necessitating the importance of designing therapeutic strategies against HIV disease progression and pathogenesis. PMID:25674514

  6. EV71-infected CD14(+) cells modulate the immune activity of T lymphocytes in rhesus monkeys.

    PubMed

    Wang, Jingjing; Pu, Jing; Huang, Hongtai; Zhang, Ying; Liu, Longding; Yang, Erxia; Zhou, Xiaofang; Ma, Na; Zhao, Hongling; Wang, Lichun; Xie, Zhenfeng; Tang, Donghong; Li, Qihan

    2013-07-01

    Preliminary studies of the major pathogen enterovirus 71 (EV71), a member of the Picornaviridae family, have suggested that EV71 may be a major cause of fatal hand, foot and mouth disease cases. Currently, the role of the pathological changes induced by EV71 infection in the immunopathogenic response remains unclear. Our study focused on the interaction between this virus and immunocytes and indicated that this virus has the ability to replicate in CD14(+) cells. Furthermore, these EV71-infected CD14(+) cells have the capacity to stimulate the proliferation of T cells and to enhance the release of certain functional cytokines. An adaptive immune response induced by the back-transfusion of EV71-infected CD14(+) cells was observed in donor neonatal rhesus monkeys. Based on these observations, the proposed hypothesis is that CD14(+) cells infected by the EV71 virus might modulate the anti-EV71 adaptive immune response by inducing simultaneous T-cell activation.

  7. Sexually transmitted infections, active component, U.S. Armed Forces, 2000-2012.

    PubMed

    2013-02-01

    This report summarizes incidence rates of the five most commonly diagnosed sexually transmitted infections (STIs) among active component service members of the U.S. Armed Forces during 2000 to 2012. Human papillomavirus (HPV) infections were the most common, followed in decreasing order of frequency by infections associated with chlamydia, herpes simplex virus, gonorrhea, and syphilis. Compared to their counterparts, women, younger service members, soldiers, and enlisted members had higher incidence rates of each STI. Rates tended to be lower among married personnel. Rates of chlamydia, HPV, and gonorrhea diagnoses were notably higher among women during 2006 to 2008 but rates of the latter two infections have since declined sharply. The relatively recent introduction of STI screening among young service women and the HPV vaccine are discussed.

  8. Contribution of Immune Activation to the Pathogenesis and Transmission of Human Immunodeficiency Virus Type 1 Infection

    PubMed Central

    Lawn, Stephen D.; Butera, Salvatore T.; Folks, Thomas M.

    2001-01-01

    The life cycle of human immunodeficiency virus type 1 (HIV-1) is intricately related to the activation state of the host cells supporting viral replication. Although cellular activation is essential to mount an effective host immune response to invading pathogens, paradoxically the marked systemic immune activation that accompanies HIV-1 infection in vivo may play an important role in sustaining phenomenal rates of HIV-1 replication in infected persons. Moreover, by inducing CD4+ cell loss by apoptosis, immune activation may further be central to the increased rate of CD4+ cell turnover and eventual development of CD4+ lymphocytopenia. In addition to HIV-1-induced immune activation, exogenous immune stimuli such as opportunistic infections may further impact the rate of HIV-1 replication systemically or at localized anatomical sites. Such stimuli may also lead to genotypic and phenotypic changes in the virus pool. Together, these various immunological effects on the biology of HIV-1 may potentially enhance disease progression in HIV-infected persons and may ultimately outweigh the beneficial aspects of antiviral immune responses. This may be particularly important for those living in developing countries, where there is little or no access to antiretroviral drugs and where frequent exposure to pathogenic organisms sustains a chronically heightened state of immune activation. Moreover, immune activation associated with sexually transmitted diseases, chorioamnionitis, and mastitis may have important local effects on HIV-1 replication that may increase the risk of sexual or mother-to-child transmission of HIV-1. The aim of this paper is to provide a broad review of the interrelationship between immune activation and the immunopathogenesis, transmission, progression, and treatment of HIV-1 infection in vivo. PMID:11585784

  9. Macrophage activation associated with chronic murine cytomegalovirus infection results in more severe experimental choroidal neovascularization.

    PubMed

    Cousins, Scott W; Espinosa-Heidmann, Diego G; Miller, Daniel M; Pereira-Simon, Simone; Hernandez, Eleut P; Chien, Hsin; Meier-Jewett, Courtney; Dix, Richard D

    2012-01-01

    The neovascular (wet) form of age-related macular degeneration (AMD) leads to vision loss due to choroidal neovascularization (CNV). Since macrophages are important in CNV development, and cytomegalovirus (CMV)-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV), laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF), an outcome that requires active virus replication. PMID:22570607

  10. Macrophage Activation Associated with Chronic Murine Cytomegalovirus Infection Results in More Severe Experimental Choroidal Neovascularization

    PubMed Central

    Cousins, Scott W.; Espinosa-Heidmann, Diego G.; Miller, Daniel M.; Pereira-Simon, Simone; Hernandez, Eleut P.; Chien, Hsin; Meier-Jewett, Courtney; Dix, Richard D.

    2012-01-01

    The neovascular (wet) form of age-related macular degeneration (AMD) leads to vision loss due to choroidal neovascularization (CNV). Since macrophages are important in CNV development, and cytomegalovirus (CMV)-specific IgG serum titers in patients with wet AMD are elevated, we hypothesized that chronic CMV infection contributes to wet AMD, possibly by pro-angiogenic macrophage activation. This hypothesis was tested using an established mouse model of experimental CNV. At 6 days, 6 weeks, or 12 weeks after infection with murine CMV (MCMV), laser-induced CNV was performed, and CNV severity was determined 4 weeks later by analysis of choroidal flatmounts. Although all MCMV-infected mice exhibited more severe CNV when compared with control mice, the most severe CNV developed in mice with chronic infection, a time when MCMV-specific gene sequences could not be detected within choroidal tissues. Splenic macrophages collected from mice with chronic MCMV infection, however, expressed significantly greater levels of TNF-α, COX-2, MMP-9, and, most significantly, VEGF transcripts by quantitative RT-PCR assay when compared to splenic macrophages from control mice. Direct MCMV infection of monolayers of IC-21 mouse macrophages confirmed significant stimulation of VEGF mRNA and VEGF protein as determined by quantitative RT-PCR assay, ELISA, and immunostaining. Stimulation of VEGF production in vivo and in vitro was sensitive to the antiviral ganciclovir. These studies suggest that chronic CMV infection may serve as a heretofore unrecognized risk factor in the pathogenesis of wet AMD. One mechanism by which chronic CMV infection might promote increased CNV severity is via stimulation of macrophages to make pro-angiogenic factors (VEGF), an outcome that requires active virus replication. PMID:22570607

  11. Salmonella infections associated with international travel: a Foodborne Diseases Active Surveillance Network (FoodNet) study.

    PubMed

    Johnson, Laura R; Gould, L Hannah; Dunn, John R; Berkelman, Ruth; Mahon, Barbara E

    2011-09-01

    Salmonella species cause an estimated 1.2 million infections per year in the United States, making it one of the most commonly reported enteric pathogens. In addition, Salmonella is an important cause of travel-associated diarrhea and enteric fever, a systemic illness commonly associated with Salmonella serotypes Typhi and Paratyphi A. We reviewed cases of Salmonella infection reported to the Centers for Disease Control and Prevention's (CDC) Foodborne Diseases Active Surveillance Network (FoodNet), a sentinel surveillance network, from 2004 to 2008. We compared travelers with Salmonella infection to nontravelers with Salmonella infection with respect to demographics, clinical characteristics, and serotypes. Among 23,712 case-patients with known travel status, 11% had traveled internationally in the 7 days before illness. Travelers with Salmonella infection tended to be older (median age, 30 years) than nontravelers (median age, 24 years; p<0.0001), but were similar with respect to gender. The most common destinations reported were Mexico (38% of travel-associated infections), India (9%), Jamaica (7%), the Dominican Republic (4%), China (3%), and the Bahamas (2%). The proportions of travelers with Salmonella infection hospitalized and with invasive disease were inversely related to the income level of the destination (p<0.0001). The most commonly reported serotypes, regardless of travel status, were Enteritidis (19% of cases), Typhimurium (14%), Newport (9%), and Javiana (5%). Among infections caused by these four serotypes, 22%, 6%, 5%, and 4%, respectively, were associated with travel. A high index of clinical suspicion for Salmonella infection is appropriate when evaluating recent travelers, especially those who visited Africa, Asia, or Latin America.

  12. Pattern of Transcription Factor Activation in Helicobacter pylori–Infected Mongolian Gerbils

    PubMed Central

    Kudo, Takahiko; Lu, Hong; Wu, Jeng–Yih; Ohno, Tomoyuki; Wu, Michael J.; Genta, Robert M.; Graham, David Y.; Yamaoka, Yoshio

    2011-01-01

    Background & Aims Helicobacter pylori interact with epithelial cells resulting in activation of cellular signaling pathways leading to an inflammatory response. The pattern and timing of transcription factor activation in H pylori-infected gastric mucosa remain unclear. We investigated the roles of transcription factors in the gastric mucosa of H pylori-infected gerbils over the course of the infection. Methods Six-week-old male Mongolian gerbils were inoculated orally with H pylori TN2GF4 or isogenic cagE mutants and examined at 1, 3, 9, and 18 months. We examined the expression of 54 transcription factors using DNA/protein arrays and electrophoretic mobility shift assays. Phosphorylation status of mitogen-activated protein kinases and I κB were evaluated by immunoblot and immunohistochemistry. Results Ten transcription factors were up-regulated by H pylori infection. Six of these factors, including activator protein-1 (AP-1) and cAMP responsive element binding protein (CREB), reached maximal levels at 3 months and were strongly correlated with cellular inflammation and ulceration. Phosphorylation of extracellular signal-regulated kinase correlated with activation of AP-1 and CREB. Levels of nuclear factor-κB and interferon-stimulated responsive element (ISRE) peaked at 18 months and correlated with the presence of severe atrophy and with phosphorylation of Jun-N-terminal kinase (JNK), p38, and IκB. Conclusions The gastric mucosal transcription factors induced by H pylori infection differed according to the phase and outcome of infection; AP-1 and CREB levels were early responders related to inflammation and ulceration, whereas NF-κB and ISRE were late responders related to atrophy. PMID:17383425

  13. Monitoring of the lactonase activity of paraoxonase-1 enzyme in HIV-1-infection.

    PubMed

    Dias, Clara; Marinho, Aline; Morello, Judit; Almeida, Gabriela; Caixas, Umbelina; Soto, Karina; Monteiro, Emilia; Pereira, Sofia

    2014-01-01

    Paraoxonase-1 (PON1) is a high-density lipoprotein (HDL)-associated enzyme known as a free radical scavenging system (1). PON-1 has three main activities, responsible for its antioxidant and anti-inflammatory potential: paraoxonase, arylesterase and lactonase (LACase), the latest to be discovered and pointed out to be its native activity (2). Among other physiological roles, the LACase might minimize the deleterious effects of hyperhomocysteinaemia in infection, by detoxifying the highly reactive metabolite homocysteine-thiolactone (HcyTL) (3),4. In the present work, we have developed and applied a method to quantify LACase activity and to explore the role of this enzyme in HIV-infection and virological response. The LACase activity was monitored in a cohort of HIV-1-infected patients, through the titration of 3-(o-hydroxyphenyl) propionic acid, formed upon the LACase-mediated hydrolysis of the substrate dihydrocoumarin. The study protocol was approved by the Ethics Committee of Centro Hospitalar de Lisboa Central and Hospital Prof. Doutor Fernando Fonseca. All patients gave their written informed consent and were adults with documented HIV-1-infection, regardless of combined antiretroviral therapy (cART) use. Naïve patients and patients who had received continuous antiretroviral treatment for more than one month were included. A total of 179 HIV-1-infected patients were included on this study (51% Men, 39% non-Caucasian, 45±13 years old). Patients with non-suppressed viraemia, either from the non-cART (n=89, 12±4 kU/L, p<0.01) or from the cART with detectable viral load (n=11, 10±5 kU/L, p<0.05) groups, had lower activity than the cART with suppressed viraemia (n=79, 15±7 kU/L) (Kruskal-Wallis test). Among naïve patients, higher viral load (> 31,500 cps/mL, Spearman r=-0.535, p=0.003) and lower CD4+ T-cells count (< 500 cell/mm(3), Pearson r=0.326, p=0.024) were associated with the LACase activity. The present study suggests that lower LACase activity is

  14. Pseudomonas aeruginosa wound infection involves activation of its iron acquisition system in response to fascial contact

    PubMed Central

    Kim, M.; Christley, S.; Khodarev, N. N.; Fleming, I.; Huang, Y.; Chang, E.; Zaborina, O.; Alverdy, J.

    2015-01-01

    Background Wound infections are traditionally thought to occur when microbial burden exceeds the innate clearance capacity of host immune system. Here we introduce the idea that the wound environment itself plays a significant contributory role to wound infection. Methods We developed a clinically relevant murine model of soft tissue infection to explore the role of activation of microbial virulence in response to tissue factors as a mechanism by which pathogenic bacteria cause wound infections. Mice underwent abdominal skin incision and light muscle injury with a crushing forceps versus skin incision alone followed by topical inoculation of P. aeruginosa. Mice were sacrificed on postoperative day 6 and abdominal tissues analyzed for clinical signs of wound infection. To determine if specific wound tissues components induce bacterial virulence, P. aeruginosa was exposed to skin, fascia, and muscle. Results Gross wound infection due to P. aeruginosa was observed to be significantly increased in injured tissues vs non-injured (80% vs 10%) tissues (n=20/group, p<0.0001). Exposure of P. aeruginosa to individual tissue components demonstrated that fascia significantly induced bacterial virulence as judged by the production of pyocyanin, a redox-active phenazine compound known to kill immune cells. Whole genome transcriptional profiling of P. aeruginosa exposed to fascia demonstrated activation of multiple genes responsible for the synthesis of the iron scavenging molecule pyochelin. Conclusion We conclude that wound elements, in particular fascia, may play a significant role in enhancing the virulence of P. aeruginosa and may contribute to the pathogenesis of clinical wound infection. PMID:25807409

  15. Mapping regions of Epstein-Barr virus (EBV) glycoprotein B (gB) important for fusion function with gH/gL

    SciTech Connect

    Plate, Aileen E.; Reimer, Jessica J.; Jardetzky, Theodore S.; Longnecker, Richard

    2011-04-25

    Glycoproteins gB and gH/gL are required for entry of Epstein-Barr virus (EBV) into cells, but the role of each glycoprotein and how they function together to mediate fusion is unclear. Analysis of the functional homology of gB from the closely related primate gammaherpesvirus, rhesus lymphocryptovirus (Rh-LCV), showed that EBV gB could not complement Rh gB due to a species-specific dependence between gB and gL. To map domains of gB required for this interaction, we constructed a panel of EBV/Rh gB chimeric proteins. Analysis showed that insertion of Rh gB from residues 456 to 807 restored fusion function of EBV gB with Rh gH/gL, suggesting this region of gB is important for interaction with gH/gL. Split YFP bimolecular complementation (BiFC) provided evidence of an interaction between EBV gB and gH/gL. Together, our results suggest the importance of a gB-gH/gL interaction in EBV-mediated fusion with B cells requiring the region of EBV gB from 456 to 807.

  16. Epstein-Barr virus envelope glycoprotein gp350 induces NF-kappaB activation and IL-1beta synthesis in human monocytes-macrophages involving PKC and PI3-K.

    PubMed

    D'Addario, M; Ahmad, A; Xu, J W; Menezes, J

    1999-12-01

    Epstein-Barr virus (EBV) is a highly immunotropic human herpesvirus with oncogenic potential and is involved in numerous pathologies. EBV utilizes its major envelope glycoprotein gp350 to bind to its receptor CR2/CD21 on target cells for initiating the infection. We have previously shown that EBV is able to modulate transcription and translation of a number of cytokine genes via its gp350-mediated binding to this receptor. However, the effects of the binding of purified gp350 to CR2/CD21 on plastic-adherent monocyte-macrophages (AMM) have not been investigated. These cells are a rich source of potent proinflammatory and immune-modulating cytokines, and express low levels of CR2/CD21. We show here for the first time that recombinant gp350 (rgp350) causes production of the potent proinflammatory cytokine IL-1beta in human AMM. Surprisingly, rgp350 is comparable in this capacity to the phorbol ester 12-0-tetradecanoylphorbol 13-acetate. This induction of IL-1beta production was accompanied by increased steady-state levels of its mRNA in gp350-treated AMM, and was dependent on the specific binding of rgp350 to the EBV receptor CR2/CD21. We also show that the signaling pathways resulting in the induction of IL-1beta synthesis by rgp350 required protein kinase C and phosphatidylinositol 3,4,5 triphosphate kinase activities and occurred via activation of the NF-kappaB family of transcription factors.-D'Addario, M., Ahmad, A., Xu, J. W., Menezes, J. Epstein-Barr virus envelope glycoprotein gp350 induces NF-kappaB activation and IL-1beta synthesis in human monocytes-macrophages involving PKC and PI3-K. PMID:10593868

  17. The capsid proteins of Aleutian mink disease virus activate caspases and are specifically cleaved during infection.

    PubMed

    Cheng, Fang; Chen, Aaron Yun; Best, Sonja M; Bloom, Marshall E; Pintel, David; Qiu, Jianming

    2010-03-01

    Aleutian mink disease virus (AMDV) is currently the only known member of the genus Amdovirus in the family Parvoviridae. It is the etiological agent of Aleutian disease of mink. We have previously shown that a small protein with a molecular mass of approximately 26 kDa was present during AMDV infection and following transfection of capsid expression constructs (J. Qiu, F. Cheng, L. R. Burger, and D. Pintel, J. Virol. 80:654-662, 2006). In this study, we report that the capsid proteins were specifically cleaved at aspartic acid residue 420 (D420) during virus infection, resulting in the previously observed cleavage product. Mutation of a single amino acid residue at D420 abolished the specific cleavage. Expression of the capsid proteins alone in Crandell feline kidney (CrFK) cells reproduced the cleavage of the capsid proteins in virus infection. More importantly, capsid protein expression alone induced active caspases, of which caspase-10 was the most active. Active caspases, in turn, cleaved capsid proteins in vivo. Our results also showed that active caspase-7 specifically cleaved capsid proteins at D420 in vitro. These results suggest that viral capsid proteins alone induce caspase activation, resulting in cleavage of capsid proteins. We also provide evidence that AMDV mutants resistant to caspase-mediated capsid cleavage increased virus production approximately 3- to 5-fold in CrFK cells compared to that produced from the parent virus AMDV-G at 37 degrees C but not at 31.8 degrees C. Collectively, our results indicate that caspase activity plays multiple roles in AMDV infection and that cleavage of the capsid proteins might have a role in regulating persistent infection of AMDV. PMID:20042496

  18. Lysis of typhus-group rickettsia-infected targets by lymphokine activated killers

    SciTech Connect

    Carl, M.; Dasch, G.A.

    1986-03-01

    The authors recently described a subset of OKT8, OKT3-positive lymphocytes from typhus-group rickettsia immune individuals which were capable of lysing autologous PHA-blasts or Epstein-Barr virus transformed B cells (LCL) infected with typhus-group rickettsiae. In order to determine if killing by these effectors was HLA-restricted, they stimulated peripheral blood mononuclear cells (PBMC) from typhus-group rickettsia immune individuals in vitro with typhus-group rickettsia-derived antigen for one week and then measured lysis of autologous LCL or HLA-mismatched LCL in a 4-6 hour Cr/sup 51/-release assay. There was significant lysis of both the autologous and the HLA-mismatched infected targets as compared to the corresponding uninfected targets. Since this suggested that the effectors were lymphokine activated killers (LAK) rather than cytotoxic T lymphocytes, they then tested this hypothesis by stimulating PBMC from both immune and non-immune individuals in vitro for one week with purified interleukin 2 and measuring lysis of infected, autologous LCL. PBMC thus treated, from both immune and non-immune individuals, were capable of significantly lysing autologous, infected LCL as compared to the non-infected control. They therefore conclude that targets infected with typhus-group rickettsiae are susceptible to lysis to LAK.

  19. Disparity of basal and therapeutically activated interferon signalling in constraining hepatitis E virus infection.

    PubMed

    Zhou, X; Xu, L; Wang, W; Watashi, K; Wang, Y; Sprengers, D; de Ruiter, P E; van der Laan, L J W; Metselaar, H J; Kamar, N; Peppelenbosch, M P; Pan, Q

    2016-04-01

    Hepatitis E virus (HEV) represents one of the foremost causes of acute hepatitis globally. Although there is no proven medication for hepatitis E, pegylated interferon-α (IFN-α) has been used as off-label drug for treating HEV. However, the efficacy and molecular mechanisms of how IFN signalling interacts with HEV remain undefined. As IFN-α has been approved for treating chronic hepatitis C (HCV) for decades and the role of interferon signalling has been well studied in HCV infection, this study aimed to comprehensively investigate virus-host interactions in HEV infection with focusing on the IFN signalling, in comparison with HCV infection. A comprehensive screen of human cytokines and chemokines revealed that IFN-α was the sole humoral factor inhibiting HEV replication. IFN-α treatment exerted a rapid and potent antiviral activity against HCV, whereas it had moderate and delayed anti-HEV effects in vitro and in patients. Surprisingly, blocking the basal IFN pathway by inhibiting JAK1 to phosphorylate STAT1 has resulted in drastic facilitation of HEV, but not HCV infection. Gene silencing of the key components of JAK-STAT cascade of the IFN signalling, including JAK1, STAT1 and interferon regulatory factor 9 (IRF9), stimulated HEV infection. In conclusion, compared to HCV, HEV is less sensitive to IFN treatment. In contrast, the basal IFN cascade could effectively restrict HEV infection. This bears significant implications in management of HEV patients and future therapeutic development. PMID:26620360

  20. Antimicrobial activity of curcumin against Helicobacter pylori isolates from India and during infections in mice.

    PubMed

    De, Ronita; Kundu, Parag; Swarnakar, Snehasikta; Ramamurthy, T; Chowdhury, Abhijit; Nair, G Balakrish; Mukhopadhyay, Asish K

    2009-04-01

    Treatment failure is a major cause of concern for the Helicobacter pylori-related gastroduodenal diseases like gastritis, peptic ulcer, and gastric cancer. Curcumin, diferuloylmethane from turmeric, has recently been shown to arrest H. pylori growth. The antibacterial activity of curcumin against 65 clinical isolates of H. pylori in vitro and during protection against H. pylori infection in vivo was examined. The MIC of curcumin ranges from 5 microg/ml to 50 microg/ml, showing its effectiveness in inhibiting H. pylori growth in vitro irrespective of the genetic makeup of the strains. The nucleotide sequences of the aroE genes, encoding shikimate dehydrogenase, against which curcumin seems to act as a noncompetitive inhibitor, from H. pylori strains presenting differential curcumin MICs showed that curcumin-mediated growth inhibition of Indian H. pylori strains may not be always dependent on the shikimate pathway. The antimicrobial effect of curcumin in H. pylori-infected C57BL/6 mice and its efficacy in reducing the gastric damage due to infection were examined histologically. Curcumin showed immense therapeutic potential against H. pylori infection as it was highly effective in eradication of H. pylori from infected mice as well as in restoration of H. pylori-induced gastric damage. This study provides novel insights into the therapeutic effect of curcumin against H. pylori infection, suggesting its potential as an alternative therapy, and opens the way for further studies on identification of novel antimicrobial targets of curcumin. PMID:19204190

  1. Infection by bacterial pathogens expressing type III secretion decreases luciferase activity: ramifications for reporter gene studies.

    PubMed

    Savkovic, S D; Koutsouris, A; Wu, G; Hecht, G

    2000-09-01

    Pathogenic microbes influence gene regulation in eukaryotic hosts. Reporter gene studies can define the roles of promoter regulatory sequences. The effect of pathogenic bacteria on reporter genes has not been examined. The aim of this study was to identify which reporter genes are reliable in studies concerning host gene regulation by bacterial pathogens expressing type III secretory systems. Human intestinal epithelial cells, T84, Caco-2 and HT-29, were transfected with plasmids containing luciferase (luc), chloramphenicol acetyltransferase (CAT) or beta-galactosidase (beta-gal) as reporter genes driven by the inducible interleukin-8 (IL-8) or constitutively active simian virus 40 (SV40) promoter. Cells were infected with enteropathogenic E. coli or Salmonella typhimurium, and the reporter activity was assessed. Luc activity significantly decreased following infection, regardless of the promoter. The activity of recombinant luc was nearly ablated by incubation with either EPEC or Salmonella in a cell-free system. Activity was partially preserved by protease inhibitors, and immunoblot analysis showed a decreased amount and molecular weight of recombinant luc, suggesting protein degradation. Neither beta-gal nor CAT activity was altered by infection. Disruption of type III secretion prevented the loss of luc activity. We conclude that CAT or beta-gal, but not luc, can be used as reliable reporter genes to assess the impact of pathogenic microbes, especially those expressing type III secretion on host cell gene regulation.

  2. Contamination of the Hospital Environment From Potential Clostridium difficile Excretors Without Active Infection.

    PubMed

    Biswas, Jason S; Patel, Amita; Otter, Jonathan A; van Kleef, Esther; Goldenberg, Simon D

    2015-08-01

    Clostridium difficile was recovered from 33 (34%) of 98 rooms of patients who were excretors compared with 36 (49%) of 73 rooms of patients with active infection. Not all laboratory algorithms can distinguish between these 2 groups, yet both may be a significant source for ongoing transmission.

  3. Ursolic Acid Activates Intracellular Killing Effect of Macrophages During Mycobacterium tuberculosis Infection.

    PubMed

    Podder, Biswajit; Jang, Woong Sik; Nam, Kung-Woo; Lee, Byung-Eui; Song, Ho-Yeon

    2015-05-01

    Tuberculosis is one of the most threatening infectious diseases to public health all over the world, for which Mycobacterium tuberculosis (MTB) is the etiological agent of pathogenesis. Ursolic acid (UA) has immunomodulatory function and exhibits antimycobacterial activity. However, the intracellular killing effect of UA has yet to be elucidated. The aim of this study was to evaluate the intracellular killing effect of UA during mycobacterial infection. The intracellular killing activity of UA was evaluated in the macrophage cell line THP-1 by the MGIT 960 system as well as by CFU count. The production of reactive oxygen species (ROS) and the level of nitric oxide (NO) were measured using DCF-DA and Griess reagent, respectively. Phagocytosis was observed by a fluorescence-based staining method, and the colony forming units were enumerated on 7H11 agar medium following infection. In addition, MRP8 mRNA expression was measured by qRT-PCR. UA significantly decreased the number of intracellular Mycobacterium through generation of ROS and NO. In addition, it profoundly activated the phagocytosis process of THP-1 cells during MTB-infection. Furthermore, our data demonstrated that UA activated the phagocytosis process in human monocyte cells through MRP8 induction. These data suggest that UA firmly contributes to the intracellular killing effect of macrophages during mycobacterial infection.

  4. Hsp90 inhibitor 17-DMAG decreases expression of conserved herpesvirus protein kinases and reduces virus production in Epstein-Barr virus-infected cells.

    PubMed

    Sun, Xiaoping; Bristol, Jillian A; Iwahori, Satoko; Hagemeier, Stacy R; Meng, Qiao; Barlow, Elizabeth A; Fingeroth, Joyce D; Tarakanova, Vera L; Kalejta, Robert F; Kenney, Shannon C

    2013-09-01

    All eight human herpesviruses have a conserved herpesvirus protein kinase (CHPK) that is important for the lytic phase of the viral life cycle. In this study, we show that heat shock protein 90 (Hsp90) interacts directly with each of the eight CHPKs, and we demonstrate that an Hsp90 inhibitor drug, 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), decreases expression of all eight CHPKs in transfected HeLa cells. 17-DMAG also decreases expression the of the endogenous Epstein-Barr virus protein kinase (EBV PK, encoded by the BGLF4 gene) in lytically infected EBV-positive cells and inhibits phosphorylation of several different known EBV PK target proteins. Furthermore, 17-DMAG treatment abrogates expression of the human cytomegalovirus (HCMV) kinase UL97 in HCMV-infected human fibroblasts. Importantly, 17-DMAG treatment decreased the EBV titer approximately 100-fold in lytically infected AGS-Akata cells without causing significant cellular toxicity during the same time frame. Increased EBV PK expression in 17-DMAG-treated AGS-Akata cells did not restore EBV titers, suggesting that 17-DMAG simultaneously targets multiple viral and/or cellular proteins required for efficient viral replication. These results suggest that Hsp90 inhibitors, including 17-DMAG, may be a promising group of drugs that could have profound antiviral effects on herpesviruses. PMID:23843639

  5. Polyomavirus JCV excretion and genotype analysis in HIV-infected patients receiving highly active antiretroviral therapy

    NASA Technical Reports Server (NTRS)

    Lednicky, John A.; Vilchez, Regis A.; Keitel, Wendy A.; Visnegarwala, Fehmida; White, Zoe S.; Kozinetz, Claudia A.; Lewis, Dorothy E.; Butel, Janet S.

    2003-01-01

    OBJECTIVE: To assess the frequency of shedding of polyomavirus JC virus (JCV) genotypes in urine of HIV-infected patients receiving highly active antiretroviral therapy (HAART). METHODS: Single samples of urine and blood were collected prospectively from 70 adult HIV-infected patients and 68 uninfected volunteers. Inclusion criteria for HIV-infected patients included an HIV RNA viral load < 1000 copies, CD4 cell count of 200-700 x 106 cells/l, and stable HAART regimen. PCR assays and sequence analysis were carried out using JCV-specific primers against different regions of the virus genome. RESULTS: JCV excretion in urine was more common in HIV-positive patients but not significantly different from that of the HIV-negative group [22/70 (31%) versus 13/68 (19%); P = 0.09]. HIV-positive patients lost the age-related pattern of JCV shedding (P = 0.13) displayed by uninfected subjects (P = 0.01). Among HIV-infected patients significant differences in JCV shedding were related to CD4 cell counts (P = 0.03). Sequence analysis of the JCV regulatory region from both HIV-infected patients and uninfected volunteers revealed all to be JCV archetypal strains. JCV genotypes 1 (36%) and 4 (36%) were the most common among HIV-infected patients, whereas type 2 (77%) was the most frequently detected among HIV-uninfected volunteers. CONCLUSION: These results suggest that JCV shedding is enhanced by modest depressions in immune function during HIV infection. JCV shedding occurred in younger HIV-positive persons than in the healthy controls. As the common types of JCV excreted varied among ethnic groups, JCV genotypes associated with progressive multifocal leukoencephalopathy may reflect demographics of those infected patient populations.

  6. Debate around infection-dependent hemophagocytic syndrome in paediatrics

    PubMed Central

    2013-01-01

    Background Hemophagocytic syndrome (HPS) is clinically defined as a combination of fever, liver dysfunction, coagulation abnormalities, pancytopenia, progressive macrophage proliferation throughout the reticuloendothelial system, and cytokine over-production, and may be primary or secondary to infectious, auto-immune, and tumoral diseases. The most consistent association is with viral infections but, as it is still debated whether any micro-organisms are involved in its pathogenesis, we critically appraised the literature concerning HPS and its relationship with infections. Discussion Infection-dependent HPS has been widely observed, but there are no data concerning its incidence in children. A better understanding of the pathophysiology of HPS may clarify the interactions between the immune system and the variously implicated potential infectious agents. Epstein-Barr virus (EBV) infection has been prominently associated with HPS, with clonal proliferation and the hyperactivation of EBV-infected T cells. However, a number of other viral, bacterial, fungal, and parasitic infections have been reported in association with HPS. In the case of low-risk HPS, corticosteroids and/or intravenous immunoglobulin or cyclosporine A may be sufficient to control the biological process, but etoposide is recommended as a means of reversing infection-dependent lymphohistiocytic dysregulation in high-risk cases. Summary HPS is a potential complication of various infections. A polymerase chain reaction search for infectious agents including EBV, cytomegalovirus and Leishmania is recommended in clinical settings characterised by non-remitting fever, organomegaly, cytopenia and hyperferritinemia. PMID:23324497

  7. Altered metabolism of gut microbiota contributes to chronic immune activation in HIV-infected individuals.

    PubMed

    Vázquez-Castellanos, J F; Serrano-Villar, S; Latorre, A; Artacho, A; Ferrús, M L; Madrid, N; Vallejo, A; Sainz, T; Martínez-Botas, J; Ferrando-Martínez, S; Vera, M; Dronda, F; Leal, M; Del Romero, J; Moreno, S; Estrada, V; Gosalbes, M J; Moya, A

    2015-07-01

    Altered interplay between gut mucosa and microbiota during treated HIV infection may possibly contribute to increased bacterial translocation and chronic immune activation, both of which are predictors of morbidity and mortality. Although a dysbiotic gut microbiota has recently been reported in HIV+ individuals, the metagenome gene pool associated with HIV infection remains unknown. The aim of this study is to characterize the functional gene content of gut microbiota in HIV+ patients and to define the metabolic pathways of this bacterial community, which is potentially associated with immune dysfunction. We determined systemic markers of innate and adaptive immunity in a cohort of HIV-infected individuals on successful antiretroviral therapy without comorbidities and in healthy non-HIV-infected subjects. Metagenome sequencing revealed an altered functional profile, with enrichment of the genes involved in various pathogenic processes, lipopolysaccharide biosynthesis, bacterial translocation, and other inflammatory pathways. In contrast, we observed depletion of genes involved in amino acid metabolism and energy processes. Bayesian networks showed significant interactions between the bacterial community, their altered metabolic pathways, and systemic markers of immune dysfunction. This study reveals altered metabolic activity of microbiota and provides novel insight into the potential host-microbiota interactions driving the sustained inflammatory state in successfully treated HIV-infected patients. PMID:25407519

  8. Altered metabolism of gut microbiota contributes to chronic immune activation in HIV-infected individuals.

    PubMed

    Vázquez-Castellanos, J F; Serrano-Villar, S; Latorre, A; Artacho, A; Ferrús, M L; Madrid, N; Vallejo, A; Sainz, T; Martínez-Botas, J; Ferrando-Martínez, S; Vera, M; Dronda, F; Leal, M; Del Romero, J; Moreno, S; Estrada, V; Gosalbes, M J; Moya, A

    2015-07-01

    Altered interplay between gut mucosa and microbiota during treated HIV infection may possibly contribute to increased bacterial translocation and chronic immune activation, both of which are predictors of morbidity and mortality. Although a dysbiotic gut microbiota has recently been reported in HIV+ individuals, the metagenome gene pool associated with HIV infection remains unknown. The aim of this study is to characterize the functional gene content of gut microbiota in HIV+ patients and to define the metabolic pathways of this bacterial community, which is potentially associated with immune dysfunction. We determined systemic markers of innate and adaptive immunity in a cohort of HIV-infected individuals on successful antiretroviral therapy without comorbidities and in healthy non-HIV-infected subjects. Metagenome sequencing revealed an altered functional profile, with enrichment of the genes involved in various pathogenic processes, lipopolysaccharide biosynthesis, bacterial translocation, and other inflammatory pathways. In contrast, we observed depletion of genes involved in amino acid metabolism and energy processes. Bayesian networks showed significant interactions between the bacterial community, their altered metabolic pathways, and systemic markers of immune dysfunction. This study reveals altered metabolic activity of microbiota and provides novel insight into the potential host-microbiota interactions driving the sustained inflammatory state in successfully treated HIV-infected patients.

  9. The effect of highly active antiretroviral therapy on liver function in human immunodeficiency virus-infected pediatric patients with or without hepatitis virus co-infection

    PubMed Central

    Wu, Lijuan; Jin, Changzhong; Bai, Shi; Davies, Henry; Rao, Heping; Liang, Yong; Wu, Nanping

    2015-01-01

    Background: Co-infection of hepatitis virus is common in human immunodeficiency virus (HIV) infected adults in China. But little is known about hepatitis virus co-infection in pediatric HIV-infected subjects. The study aimed to investigate the impact of hepatitis B virus (HBV) and/or hepatitis C virus (HCV) co-infection and highly active antiretroviral therapy (HAART) on liver function of pediatric HIV-infected subjects. Materials and Methods: A cohort study including 101 pediatric HIV-infected subjects with HBV/HCV co-infection and 44 pediatric comparators with HIV mono-infection was carried out in Henan Province of China from September 2011 to September 2012. All patients received HAART for 1-year. HBV and HCV infection was determined by antibody tests. HIV RNA load, CD4+ T-cell counts and liver function were determined before and after HAART. The Student's t-test or a one-way ANOVA was used for normally distributed values and A Mann-Whitney U-test was performed for values without normal distribution using SPSS statistical package 18.0 (SPSS Inc.). Results: After HAART for 1-year, the median levels of viral load were decreased to lower limit of detection in 90.34% pediatric HIV-infected subjects with/without HBV/HCV co-infection (P < 0.001), and CD4+ T-cell counts increased significantly (P < 0.001). Compared with the pre-HAART, mean level of alanine aminotransferase (ALT) in each group had a significant increase after HAART (P < 0.01). The mean levels of ALT and aspartate aminotransferase (AST) in nevirapine (NVP) based HAART group increased significantly after HAART (P < 0.01). Mean change values of ALT and AST were significantly higher in the NVP based regimen group than in the efavirenz (EFV) based regimen group (P < 0.01). For HIV/HBV/HCV co-infected patients, mean change values of ALT and AST in NVP-based HAART group was significantly higher than that in EFV-based HAART group (P < 0.01). Conclusion: Highly active antiretroviral therapy can damage liver

  10. NTPDase and 5'-nucleotidase activities in synaptosomes of rabbits experimentally infected with BoHV-5.

    PubMed

    da Silva, Cássia B; Paim, Francine C; Wolkmer, Patricia; Abdalla, Fátima H; Carvalho, Fabiano B; Palma, Heloísa H; Mello, Camila B E; Flores, Eduardo F; Andrade, Cinthia M; Lopes, Sonia T A

    2015-10-01

    Bovine herpesvirus type 5 (BoHV-5) is the causative agent of herpetic meningoencephalitis in cattle. The purinergic system is described as a modulator of the immune response and neuroinflammation. These functions are related to the extracellular nucleotides concentration. NTPDase and 5'-nucleotidase are enzymes responsible for controlling the extracellular concentration of adenosine triphosphate (ATP), adenosine diphosphate (ADP), adenosine monophosphate (AMP), and adenosine (ADO). The aim of this study is to determinate the ectonucleotidase activity in cortical synaptosomes and synaptosomes from the hippocampus of rabbits experimentally infected with BoHV-5. Rabbits were divided into four groups, two control groups (non-inoculated animals), and two infected groups (inoculated with BoHV-5). The infected groups received 0.5 ml of BoHV-5 suspension with 10(7.5)TCID50 of viral strain SV-507/99, per paranasal sinuses, and the control groups received 0.5 ml of minimum essential media per paranasal sinuses. Animals were submitted to euthanasia on days 7 and 12 post-inoculation (p.i.); cerebral cortex and hippocampus were collected for the synaptosomes isolation and posterior determination of the ectonucleotidase activities. The results showed a decrease (P < 0.05) in ectonucleotidase activity in synaptosomes from the cerebral cortex of infected rabbits, whereas an increased (P < 0.05) ectonucleotidase activity was observed in synaptosomes from the hippocampus. These differences may be related with the heterogeneous distribution of ectonucleotidases in the different brain regions and also with the viral infectivity. Therefore, it is possible to speculate that BoHV-5 replication results in changes in ectonucleotidase activity in the brain, which may contribute to the neurological signs commonly observed in this disease.

  11. Accumulation and activation of natural killer cells in local intraperitoneal HIV-1/MuLV infection results in early control of virus infected cells.

    PubMed

    Johansson, Susanne E; Brauner, Hanna; Hinkula, Jorma; Wahren, Britta; Berg, Louise; Johansson, Maria H

    2011-01-01

    Natural killer (NK) cells are important effectors in resistance to viral infections. The role of NK cells in the acute response to human immunodeficiency virus 1 (HIV-1) infected cells was investigated in a mouse model based on a HIV-1/murine leukemia virus (MuLV) pseudovirus. Splenocytes infected with HIV-1/MuLV were injected intraperitoneally and local immunologic responses and persistence of infected cells were investigated. In vivo depletion with an anti-NK1.1 antibody showed that NK cells are important in resistance to virus infected cells. Moreover, NK cell frequency in the peritoneal cavity increased in response to infected cells and these NK cells had a more mature phenotype, as determined by CD27 and Mac-1 expression. Interestingly, after injection of HIV-1/MuLV infected cells, but not MuLV infected cells, peritoneal NK cells had an increased cytotoxic activity. In conclusion, NK cells play a role in the early control of HIV-1/MuLV infected cells in vivo.

  12. Activity of 5-chloro-pyrazinamide in mice infected with Mycobacterium tuberculosis or Mycobacterium bovis

    PubMed Central

    Ahmad, Zahoor; Tyagi, Sandeep; Minkowski, Austin; Almeida, Deepak; Nuermberger, Eric L.; Peck, Kaitlin M.; Welch, John T.; Baughn, Anthony D.; Jacobs, Williams R.; Grosset, Jacques H.

    2012-01-01

    Background & objectives: Pyrazinamide is an essential component of first line anti-tuberculosis regimen as well as most of the second line regimens. This drug has a unique sterilizing activity against Mycobacterium tuberculosis. Its unique role in tuberculosis treatment has lead to the search and development of its structural analogues. One such analogue is 5-chloro-pyrazinamide (5-Cl-PZA) that has been tested under in vitro conditions against M. tuberculosis. The present study was designed with an aim to assess the activity of 5-Cl-PZA, alone and in combination with first-line drugs, against murine tuberculosis. Methods: The minimum inhibitory concentration (MIC) of 5-Cl-PZA in Middlebrook 7H9 broth (neutral pH) and the inhibitory titre of serum from mice that received a 300 mg/kg oral dose of 5-Cl-PZA 30 min before cardiac puncture were determined. To test the tolerability of orally administered 5-Cl-PZA, uninfected mice received doses up to 300 mg/kg for 2 wk. Four weeks after low-dose aerosol infection either with M. tuberculosis or M. bovis, mice were treated 5 days/wk with 5-Cl-PZA, at doses ranging from 37.5 to 150 mg/kg, either alone or in combination with isoniazid and rifampicin. Antimicrobial activity was assessed by colony-forming unit counts in lungs after 4 and 8 wk of treatment. Results: The MIC of 5-Cl-PZA against M. tuberculosis was between 12.5 and 25 μg/ml and the serum inhibitory titre was 1:4. Under the same experimental conditions, the MIC of pyrazinamide was >100 μg/ml and mouse serum had no inhibitory activity after a 300 mg/kg dose; 5-Cl-PZA was well tolerated in uninfected and infected mice up to 300 and 150 mg/kg, respectively. While PZA alone and in combination exhibited its usual antimicrobial activity in mice infected with M. tuberculosis and no activity in mice infected with M. bovis, 5-Cl-PZA exhibited antimicrobial activity neither in mice infected with M. tuberculosis nor in mice infected with M. bovis. Interpretation

  13. Mycobacterium avium serovars 2 and 8 infections elicit unique activation of the host macrophage immune responses.

    PubMed

    Cebula, B R; Rocco, J M; Maslow, J N; Irani, V R

    2012-12-01

    Mycobacterium avium is an opportunistic pathogen whose pathogenesis is attributed to its serovar-specific glycopeptidolipid (ssGPL), which varies among its 31 serovars. To determine if the presence and type of ssGPLs contribute to M. avium pathogenesis, we infected murine macrophages (mφs) with two M. avium wild type (wt) serovars (2 and 8) and their serovar-null strains. We examined the influence of ssGPL (presence and type) on cytokine production in non-activated (-IFN-γ) and activated (+IFN-γ) mφs, and the bacterial intra-mφ survival over a 6-day infection process. Serovar-2 infections activated TNF-α production that increased over the 6 day period and was capable of controlling the intra-mφ serovar-2 null strain. In contrast, the serovar-8 infection stimulated a strong pro-inflammatory response, but was incapable of removing the invading pathogen, maybe through IL-10 production. It was clear that the intracellular growth of serovar-null in contrast to the wt M. avium strains was easily controlled. Based on our findings and the undisputed fact that M. avium ssGPL is key to its pathogenesis, we conclude that it is not appropriate to dissect the pathogenesis of one M. avium serovar and apply those findings to other serovars. PMID:22991047

  14. Highly heterogeneous, activated and short-lived regulatory T cells during chronic filarial infection

    PubMed Central

    Metenou, Simon; Coulibaly, Yaya I.; Sturdevant, Daniel; Dolo, Housseini; Diallo, Abdallah A.; Soumaoro, Lamine; Coulibaly, Michel E.; Kanakabandi, Kishore; Porcella, Stephen F.; Klion, Amy D.; Nutman, Thomas B.

    2016-01-01

    The mechanisms underlying the increase in the numbers of regulatory T (Treg) cells in chronic infection settings remain unclear. Here we have delineated the phenotype and transcriptional profiles of Treg cells from 18 filarial-infected (Fil+) and 19 filarial-uninfected (Fil-) subjects. We found that the frequencies of Foxp3+ Treg cells expressing CTLA-4, GITR, LAG-3 and IL-10 were significantly higher in Fil+ subjects compared with that in Fil- subjects. Foxp3-expressing Treg-cell populations in Fil+ subjects were also more heterogeneous and had higher expression of IL-10, CCL-4, IL-29, CTLA-4 and TGF-β than Fil- subjects, each of these cytokines having been implicated in immune suppression. Moreover, Foxp3-expressing Treg cells from Fil+ subjects had markedly upregulated expression of activation-induced apoptotic genes with concomitant downregulation of those involved in cell survival. To determine whether the expression of apoptotic genes was due to Treg-cell activation, we found that the expression of CTLA-4, CDk8, RAD50, TNFRSF1A, FOXO3 and RHOA were significantly upregulated in stimulated cells compared with unstimulated cells. Taken together, our results suggest that in patent filarial infection, the expanded Treg-cell populations are heterogeneous, short-lived, activated and express higher levels of molecules known to modulate immune responsiveness, suggesting that filarial infection is associated with high Treg-cell turnover. PMID:24737144

  15. Evaluation of the Microbicidal Activity and Cytokines/Chemokines Profile Released by Neutrophils from HTLV-1-Infected Individuals

    PubMed Central

    Bezerra, Caroline A.; Cardoso, Thiago M.; Giudice, Angela; Porto, Aurélia F.; Santos, Silvane B.; Carvalho, Edgar M.; Bacellar, Olívia

    2011-01-01

    Human T cell lymphotropic virus type-1 (HTLV-1) induces activation and spontaneous proliferation of T cells with production of type-1 pro-inflammatory cytokines. It modifies the immune response to other antigens and increases susceptibility to infectious diseases. However, little is known about innate immunity in HTLV-1 infection. HTLV-1-infected individuals have higher spontaneous neutrophil activation than HTLV-1-seronegative individuals, as shown by the nitroblue tetrazolium (NBT) assay. This study was conducted to evaluate neutrophil function in HTLV-1-infected individuals. Participants in the study included 18 HTLV-1-infected individuals and 14 HTLV-1-seronegative controls. We evaluated the ability of neutrophils (PMNs) to control a parasite infection, to produce peroxynitrite, cytokines and chemokines and to express activation markers in cultures when stimulated with LPS or infected with Leishmania. When compared with the control group, there was no difference in the percentage of PMNs infected with Leishmania or in the number of amastigotes/100 PMNs in HTLV-1-infected individuals. The microbicidal activity of the PMNs and the levels of CXCL8 and CCL4 released by these cells did not show a difference between HTLV-1-infected individuals and the control group. In both the HTLV-1 group and the control group, infection with Leishmania or stimulation of PMNs led to cellular activation. These observations suggest that neutrophils from HTLV-1-infected individuals have preserved their ability to become activated and to produce chemokines and peroxynitrite after stimulation and that the susceptibility to infection by intracellular Leishmania amazonensis in HTLV-1-infected individuals does not depend on impairment of neutrophil function. PMID:21595736

  16. Immunomodulating and antiviral activities of Uncaria tomentosa on human monocytes infected with Dengue Virus-2.

    PubMed

    Reis, Sonia Regina I N; Valente, Ligia M M; Sampaio, André L; Siani, Antonio C; Gandini, Mariana; Azeredo, Elzinandes L; D'Avila, Luiz A; Mazzei, José L; Henriques, Maria das Graças M; Kubelka, Claire F

    2008-03-01

    Uncaria tomentosa (Willd.) DC., a large woody vine native to the Amazon and Central American rainforests has been used medicinally by indigenous peoples since ancient times and has scientifically proven immunomodulating, anti-inflammatory, cytotoxic and antioxidant activities. Several inflammatory mediators that are implicated in vascular permeability and shock are produced after Dengue Virus (DENV) infection by monocytes, the primary targets for virus replication. Here we assessed the immunoregulatory and antiviral activities from U. tomentosa-derived samples, which were tested in an in vitro DENV infection model. DENV-2 infected human monocytes were incubated with U. tomentosa hydro-alcoholic extract or either its pentacyclic oxindole alkaloid-enriched or non-alkaloid fractions. The antiviral activity was determined by viral antigen (DENV-Ag) detection in monocytes by flow cytometry. Our results demonstrated an in vitro inhibitory activity by both extract and alkaloidal fraction, reducing DENV-Ag+ cell rates in treated monocytes. A multiple microbead immunoassay was applied for cytokine determination (TNF-alpha, IFN-alpha, IL-6 and IL-10) in infected monocyte culture supernatants. The alkaloidal fraction induced a strong immunomodulation: TNF-alpha and IFN-alpha levels were significantly decreased and there was a tendency towards IL-10 modulation. We conclude that the alkaloidal fraction was the most effective in reducing monocyte infection rates and cytokine levels. The antiviral and immunomodulating in vitro effects from U. tomentosa pentacyclic oxindole alkaloids displayed novel properties regarding therapeutic procedures in Dengue Fever and might be further investigated as a promising candidate for clinical application.

  17. Dengue Virus Infection of Mast Cells Triggers Endothelial Cell Activation

    PubMed Central

    Brown, Michael G.; Hermann, Laura L.; Issekutz, Andrew C.; Marshall, Jean S.; Rowter, Derek; Al-Afif, Ayham; Anderson, Robert

    2011-01-01

    Vascular perturbation is a hallmark of severe forms of dengue disease. We show here that antibody-enhanced dengue virus infection of primary human cord blood-derived mast cells (CBMCs) and the human mast cell-like line HMC-1 results in the release of factor(s) which activate human endothelial cells, as evidenced by increased expression of the adhesion molecules ICAM-1 and VCAM-1. Endothelial cell activation was prevented by pretreatment of mast cell-derived supernatants with a tumor necrosis factor (TNF)-specific blocking antibody, thus identifying TNF as the endothelial cell-activating factor. Our findings suggest that mast cells may represent an important source of TNF, promoting vascular endothelial perturbation following antibody-enhanced dengue virus infection. PMID:21068256

  18. Activation of pulmonary and lymph node dendritic cells during chronic Pseudomonas aeruginosa lung infection in mice.

    PubMed

    Damlund, Dina Silke Malling; Christophersen, Lars; Jensen, Peter Østrup; Alhede, Morten; Høiby, Niels; Moser, Claus

    2016-06-01

    The majority of cystic fibrosis (CF) patients acquire chronic Pseudomonas aeruginosa lung infection, resulting in increased mortality and morbidity. The chronic P. aeruginosa lung infection is characterized by bacteria growing in biofilm surrounded by polymorphonuclear neutrophils (PMNs). However, the infection is not eradicated and the inflammatory response leads to gradual degradation of the lung tissue. In CF patients, a Th2-dominated adaptive immune response with a pronounced antibody response is correlated with poorer outcome. Dendritic cells (DCs) are crucial in bridging the innate immune system with the adaptive immune response. Once activated, the DCs deliver a set of signals to uncommitted T cells that induce development, such as expansion of regulatory T cells and polarization of Th1, Th2 or Th17 subsets. In this study, we characterized DCs in lungs and regional lymph nodes in BALB/c mice infected using intratracheal installation of P. aeruginosa embedded in seaweed alginate in the lungs. A significantly elevated concentration of DCs was detected earlier in the lungs than in the regional lymph nodes. To evaluate whether the chronic P. aeruginosa lung infection leads to activation of DCs, costimulatory molecules CD80 and CD86 were analyzed. During infection, the DCs showed significant elevation of CD80 and CD86 expression in both the lungs and the regional lymph nodes. Interestingly, the percentage of CD86-positive cells was significantly higher than the percentage of CD80-positive cells in the lymph nodes. In addition, cytokine production from Lipopolysaccharides (LPS)-stimulated DCs was analyzed demonstrating elevated production of IL-6, IL-10 and IL-12. However, production of IL-12 was suppressed earlier than IL-6 and IL-10. These results support that DCs are involved in skewing of the Th1/Th2 balance in CF and may be a possible treatment target. PMID:27009697

  19. Cutting edge: miR-223 and EBV miR-BART15 regulate the NLRP3 inflammasome and IL-1β production.

    PubMed

    Haneklaus, Moritz; Gerlic, Motti; Kurowska-Stolarska, Mariola; Rainey, Ashleigh-Ann; Pich, Dagmar; McInnes, Iain B; Hammerschmidt, Wolfgang; O'Neill, Luke A J; Masters, Seth L

    2012-10-15

    Although microRNA (miRNA) regulation of TLR signaling is well established, this has not yet been observed for NLR proteins or the inflammasomes they form. We have now validated a highly conserved miR-223 target site in the NLRP3 3'-untranslated region. miR-223 expression decreases as monocytes differentiate into macrophages, whereas NLRP3 protein increases during this time. However, overexpression of miR-223 prevents accumulation of NLRP3 protein and inhibits IL-1β production from the inflammasome. Virus inhibition of the inflammasome is an emerging theme, and we have also identified an EBV miRNA that can target the miR-223 binding site in the NLRP3 3'-untranslated region. Furthermore, this virus miRNA can be secreted from infected B cells via exosomes to inhibit the NLRP3 inflammasome in noninfected cells. Therefore, we have identified both the first endogenous miRNA that limits NLRP3 inflammatory capacity during myeloid cell development and also a viral miRNA that takes advantage of this, limiting inflammation for its own purposes. PMID:22984081

  20. Hybrid spreading mechanisms and T cell activation shape the dynamics of HIV-1 infection.

    PubMed

    Zhang, Changwang; Zhou, Shi; Groppelli, Elisabetta; Pellegrino, Pierre; Williams, Ian; Borrow, Persephone; Chain, Benjamin M; Jolly, Clare

    2015-04-01

    HIV-1 can disseminate between susceptible cells by two mechanisms: cell-free infection following fluid-phase diffusion of virions and by highly-efficient direct cell-to-cell transmission at immune cell contacts. The contribution of this hybrid spreading mechanism, which is also a characteristic of some important computer worm outbreaks, to HIV-1 progression in vivo remains unknown. Here we present a new mathematical model that explicitly incorporates the ability of HIV-1 to use hybrid spreading mechanisms and evaluate the consequences for HIV-1 pathogenenesis. The model captures the major phases of the HIV-1 infection course of a cohort of treatment naive patients and also accurately predicts the results of the Short Pulse Anti-Retroviral Therapy at Seroconversion (SPARTAC) trial. Using this model we find that hybrid spreading is critical to seed and establish infection, and that cell-to-cell spread and increased CD4+ T cell activation are important for HIV-1 progression. Notably, the model predicts that cell-to-cell spread becomes increasingly effective as infection progresses and thus may present a considerable treatment barrier. Deriving predictions of various treatments' influence on HIV-1 progression highlights the importance of earlier intervention and suggests that treatments effectively targeting cell-to-cell HIV-1 spread can delay progression to AIDS. This study suggests that hybrid spreading is a fundamental feature of HIV infection, and provides the mathematical framework incorporating this feature with which to evaluate future therapeutic strategies. PMID:25837979

  1. Activation-induced apoptosis in peripheral blood mononuclear cells during hepatosplenic Schistosoma mansoni infections.

    PubMed

    Ghoneim, H M; Demian, S R; Heshmat, M G; Ismail, N S; El-Sayed, Laila H

    2008-01-01

    It is well established that programmed cell death (apoptosis) is an important regulator of host responses during infection with a variety of intra- and extra-cellular pathogens. The present work aimed at assessment of in vitro spontaneous and phytohemagglutinin (PHA)-induced apoptosis in mononuclear cells isolated from patients with hepatosplenic form of S. mansoni infections. Cell death data were correlated to the degree of lymphoproliferative responses to PHA as well as to the serum anti-schistosomal antibody titers. A markedly significant increase in PHA-induced apoptosis in lymphocytes isolated from S. mansoni-infected patients was seen when compared to the corresponding healthy controls. However, a slight difference was recorded between the two studied groups regarding the spontaneous apoptosis. This was accompanied with a significant impairment of in vitro PHA-induced lymphoproliferation of T cells from S. mansoni patients. Data of the present study supports the hypothesis that activation-induced cell death (AICD) is a potentially contributing factor in T helper (Th) cell regulation during chronic stages of schistosomiasis, which represents a critically determinant factor in the host-parasite interaction and might influence the destiny of parasitic infections either towards establishment of chronic infection or towards host death.

  2. Activation-induced apoptosis in peripheral blood mononuclear cells during hepatosplenic Schistosoma mansoni infections.

    PubMed

    Ghoneim, H M; Demian, S R; Heshmat, M G; Ismail, N S; El-Sayed, Laila H

    2008-01-01

    It is well established that programmed cell death (apoptosis) is an important regulator of host responses during infection with a variety of intra- and extra-cellular pathogens. The present work aimed at assessment of in vitro spontaneous and phytohemagglutinin (PHA)-induced apoptosis in mononuclear cells isolated from patients with hepatosplenic form of S. mansoni infections. Cell death data were correlated to the degree of lymphoproliferative responses to PHA as well as to the serum anti-schistosomal antibody titers. A markedly significant increase in PHA-induced apoptosis in lymphocytes isolated from S. mansoni-infected patients was seen when compared to the corresponding healthy controls. However, a slight difference was recorded between the two studied groups regarding the spontaneous apoptosis. This was accompanied with a significant impairment of in vitro PHA-induced lymphoproliferation of T cells from S. mansoni patients. Data of the present study supports the hypothesis that activation-induced cell death (AICD) is a potentially contributing factor in T helper (Th) cell regulation during chronic stages of schistosomiasis, which represents a critically determinant factor in the host-parasite interaction and might influence the destiny of parasitic infections either towards establishment of chronic infection or towards host death. PMID:20306689

  3. Infection of Ustilaginoidea virens intercepts rice seed formation but activates grain‐filling‐related genes

    PubMed Central

    Fan, Jing; Guo, Xiao‐Yi; Li, Liang; Huang, Fu; Sun, Wen‐Xian; Li, Yan; Huang, Yan‐Yan; Xu, Yong‐Ju; Shi, Jun; Lei, Yang; Zheng, Ai‐Ping

    2015-01-01

    Abstract Rice false smut has become an increasingly serious disease in rice (Oryza sativa L.) production worldwide. The typical feature of this disease is that the fungal pathogen Ustilaginoidea virens (Uv) specifically infects rice flower and forms false smut ball, the ustiloxin‐containing ball‐like fungal colony, of which the size is usually several times larger than that of a mature rice seed. However, the underlying mechanisms of Uv‐rice interaction are poorly understood. Here, we applied time‐course microscopic and transcriptional approaches to investigate rice responses to Uv infection. The results demonstrated that the flower‐opening process and expression of associated transcription factors, including ARF6 and ARF8, were inhibited in Uv‐infected spikelets. The ovaries in infected spikelets were interrupted in fertilization and thus were unable to set seeds. However, a number of grain‐filling‐related genes, including seed storage protein genes, starch anabolism genes and endosperm‐specific transcription factors (RISBZ1 and RPBF), were highly transcribed as if the ovaries were fertilized. In addition, critical defense‐related genes like NPR1 and PR1 were downregulated by Uv infection. Our data imply that Uv may hijack host nutrient reservoir by activation of the grain‐filling network because of growth and formation of false smut balls. PMID:25319482

  4. Therapeutic and prophylactic activity of itraconazole against human rhinovirus infection in a murine model

    PubMed Central

    Shim, Aeri; Song, Jae-Hyoung; Kwon, Bo-Eun; Lee, Jeong-Jun; Ahn, Jae-Hee; Kim, Yeon-Jeong; Rhee, Ki-Jong; Chang, Sun-Young; Cha, Younggil; Lee, Yong-Soo; Kweon, Mi-Na; Park, Kwi Sung; Kim, Dong-Eun; Cho, Sungchan; Cho, Hyun-Jong; Ko, Hyun-Jeong

    2016-01-01

    Human rhinovirus (HRV) is the most common viral infectious agent in humans and is the predominant cause of the common cold. There is a need for appropriate vaccines or therapeutic agents to treat HRV infection. In this study, we investigated whether itraconazole (ICZ) can protect cells from HRV-induced cytotoxicity. Replication of HRV1B was reduced by ICZ treatment in the lungs of HRV1B- as compared to vehicle-treated mice. The numbers of immune cells, including granulocytes and monocytes, were reduced in bronchoalveolar lavage fluid (BALF) by ICZ administration after HRV1B infection, corresponding to decreased pro-inflammatory cytokine and chemokine levels in BALF. A histological analysis of lung tissue showed that ICZ suppressed inflammation caused by HRV1B infection. Interestingly, pretreatment of mice with ICZ in the form of a nasal spray had potent prophylactic antiviral activity. Cholesterol accumulation in the plasma membrane was observed upon HRV infection; ICZ blocked cholesterol trafficking to the plasma membrane, as well as resulted in its accumulation in subcellular compartments near the nucleus. These findings suggest that ICZ is a potential antiviral agent for the treatment of HRV infection, which can be adopted preventatively as well as therapeutically. PMID:26976677

  5. The anti-infective activity of punicalagin against Salmonella enterica subsp. enterica serovar typhimurium in mice.

    PubMed

    Li, Guanghui; Feng, Yuqing; Xu, Yunfeng; Wu, Qian; Han, Qi'an; Liang, Xiujun; Yang, Baowei; Wang, Xin; Xia, Xiaodong

    2015-07-01

    Punicalagin, a major bioactive component of pomegranate peel, has been proven to have antioxidant, antiviral, anti-apoptosis, and hepatoprotective properties. The aim of this study was to investigate the anti-infective activity of punicalagin in a mouse model. C57BL/6 mice were initially challenged with Salmonella enterica subsp. enterica serovar typhimurium (S. typhimurium) and then treated with punicalagin. Food and water consumption and body weight were recorded daily. On day 8 post infection, the mice were sacrificed to examine pathogen counts in tissues, hematological parameters, cytokine levels, and histological changes. Compared to mice only infected with S. typhimurium, punicalagin-treated mice had more food consumption and less weight loss. A higher survival rate and lower counts of viable S. typhimurium in feces, liver, spleen, and kidney were found in the punicalagin-treated mice. The enzyme link